Download vveather proverbs paradoxes

VVEATHER PROVERBS
AND
PARADOXES
BY
W.
J. HUMPHREYS, 'Ph.D.
Meteorological Physicist, United Stales Weather l}ljP!]!jJ,f
author of "Physics of the Air"
BALTIMORE
WILLIAMS & WILKINS COMPANY
1923
COPYRIGHT
1923
WILLIAMS & WILKINS COMPANY
Made in United States 'oj America
Published September, 1923
COMPOSED AND 'PRINTED AT THE
WAVERJ;;Y PRESS
BY THE WILLIAMS & WILKINS COMPANY
BALl'IMORE, MARYLAND, U. S. J\.
CONTENTS
PAGE
Preface .........
I
• • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • ••
PART
vii
I
VVeather lDroverbs
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seasons........ .....................................
Sun..... . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . .. . . . . . . ..
The Green Ray. . ...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
'Sky Colors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Rainbow...........................................
Coronas and Halos ................................. "
Moon ..............................................
Stars...... ..................... ....................
Fogs...............................................
Clouds.. ...........................................
Rain.... .............. ............ .................
Dew and Frost ..................................... .
Wind ............................................. .
Barometer......................................... '.
Thunder............................... ,............ .
Sound ............................................. .
St. Elmo's Fire ........... , ......................... .
Tide .............................................. .
Odors ............................................. .
Springs and Wells .................................... .
Hairs, strings, and other things ....................... .
Smoke .... , ........................................ .
Plants....... .......................................
Birds and Beasts.................................... .
Aches and Pains .................................... .
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CONTENTS
PART II
Meteorological Paradoxes
Introduction. " . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Airpushed north blows east. ...............
Rain dries the air...... . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
More air goes up than ever comes down. . . . . . . . . . . . . . ..
To cool air, heat it. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
To warm air, cool it. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Not air that is heated, but air that is not heated, is thereby
warmed ................................. '. . . . . . . ..
Not air that is chilled, but air that is not chilled, is 'thereby
cooled ............................................
Mixing brings air to a non-uniform temperature. . . . . . . ..
The nearer the sun, the colder the air .... : . . . . . . . . . . . ..
The coldest air covers the warmest earth. . . . . . . . . . . . . ..
As the days grow longer, the cold grows stronger ........
As the nights g,row long,er, the heat g,rows stronger .......
As the sun descends, the temperature ascends ...........
When the thaw comes on, the frost goes down ...........
The absolute maximum diurnal insolation (heat supply) is
at the south pole ..................................
The hotter the sun, the colder the earth. . . . . . . . . . . . . . ..
The cooler the sun, the warmer the earth. . . . . . . . . . . . . ..
The colder the day, the hotter the sun ..................
The closer the sun, the colder the season. . . . . . . . . . . . . . ..
The sun rises before it is up. . . . . . . . . . . . . . . . . . . . . . . . . ..
The sun sets after it is down ............... '.' . . . . . . . ..
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ILLUSTRATIONS
FACING PAGE
Rainbow .......•.....................................
Corona ..............................................
Halo .............................................. :.
Fog, radiation ................................ , . . . . . ..
Fog, advection or drift ............................... ,
Fracto-stratus, scud,-:mIst. . . . . .. . . . . . . . . . . . . . . . . . . . . . ..
Cumulus ............................................
Cumulus and fracto-cumulus .......................... ,
. Alto-cumulus, "mackerel scales" ....................... ,
Alto-cumulus and cirro-cumulus ........................
Cirrus, "mares' tails," "painter's brush" ................ ,
Cumulus ............................................
Cumulus .............................................
Cumulo-nimbus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ..
Lightning............................................
Crepuscular Rays, "Sun drawing water" .................
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FIGURES IN TEXT
_
NU
1. How air pushed one way blows another.... . . . . . . . . . .. 90
2. Vertical temperature gradients of free air ........... , ., 95
PREFACE
There are several good collections of weather
proverbs, good in the encyclopedic sense of
including everything, but none of them, not
even Mr. Richard Inwards' delightful and surprisingly extensive Weather Lore, makes any
attempt to separate the true and helpful from
the false and misleading. These books are
·interesting·as folk-lore, but they are not useful
as weather guides, for, making no distinction
between the good and the bad, they jumble all
together as of equal importance-rational proverbs, based on abundant and accurate observations, mere assertions, unsupported by facts, and
utterly silly sayings that originated in sheer
superstition. No wonder, then, all alike have
come at least into disrepute. If, however, the
few weather proverbs that are essentially correct
could only be gotten away from their innumerable bad associates, and endowed with the
dignity of logical explanations, they would, it is
believed, at once be respected and soon become
useful. The first part of this book, based on an
article in the Popular Science Monthly, May,
1911, is an effort to make that desirable rescue,
and to show that those saved are indeed rational
and full of good service.
vii
viii
PREFACE
Paradoxes, too, like the terse proverb, are
interesting, instructive, and mnemonk-they
fix things in the memory. Hence, perhaps, the
second part of the book, based on 'an article in
the Journal of the Washington Academy of
Sciences, March 19, 1920, is also justified.
These two parts are put under a single cover
for convenience, each being smaIl, and because
they really go well together as a Meteorological
Miscellany.
Those who wish to know more merely of the
ways of the wind and the weather should consult
a modem work on Meteorology, Those, however, who are ambitious to understand the
causes of these ways, as also of the rainbow,
the halo, the thunderstorm, the aurora and the
many other interesting phenomena of the sky,
might read Physics of the Air, published by the
Franklin Institute of Philadelphia, Pa., and
the various original articles there referred to.
The subject is vast and in one asp~ct or allother
meets every whim and. taste--charming to the
aesthetic, profitable to the frugal, and challenging to the studious.
The author desires to express· his thanks and.
appreciation to the Fran'klin Institute of Philadelphia for their courtesy in allowing the use of
numerous illustrations.
PART I
Weather Proverbs
INTRODUCTTI9N
"So it falls that all men are
With fine weather happier far."
-KING ALFRED.
This thousand-year-old observation by England's wisest ruler recognizes the fact that fine
·weather induces good tempers, and therefore
amply justifies the proverb that shrewdly bids
one to "Do business with men when the wind
is in the northwest," justifies it because when
the wind is from that direction at any place in
the temperate zone of the northern hemisphere,
the region to which this proverb applies, the
weather there is likely then to be fine and
bracing, and hence one's mood buoyant, cheerful and hopeful-his best possible state for
quick decision and bold enterprise.
But this effect on the minds of men does not
exhaust the good and the evil of weather conditions, for our comfort, our convenience, and
even the success or failure of whatever we undertake, all depend, in large measure, upon clear
skies and cloudy, upon wind and rain, and
upon everything else that renders the elements
fair or foul. As wittily and truthfully said:
3
4
WEATHER PROV.ERBS
•
"What is it moulds the life of man?
The weather.
What makes some black and others tan?
The weather.
What makes the Zulu live in trees;
And Congo natives dress in leaves
While others go in furs and freeze?
The weather."
Because, then, of the great influence weather
conditions have over human affairs numerous
rules for foretelling the coming of weather·
changes have been formulated in all ages and
by all peoples. Many of these rules are applicable nearly everywhere, but many others, as
one might suspect, owe their justification to
some peculiar configuration of mountain and
valley, or distribution of land and water, and
hence, when transferred to other places commonly are meaningless, if not even misleading,
while a still larger number, born of fancy or
superstition, are of no use anywhere. Never.
theless, all of them, the wise and the silly, the
good and the' bad, have been inherited alike
from the ends of the earth-have become
weather nuggets in that great vein of wisdom
and folly called folk-lore.
Some of these nuggets are as pure gold, for
they correctly state the actual order, or sequence,
of weather phenomena, as qetermined by in-
WEA1HER PROVERBS
5
numerable observations, determined even when
the cause for such an order was not in the least
understood by those who discovered it, but, as
already stated, most of them are as only fools'
gold, alluringly pretty, but wholly deceptive.
To this latter class belong hundreds of proverbs
of the ground-hog and goose-bone type, some
owing their origin to one thing and some to
another, but, like predictions based on the
weather of saints' days, or on the phase of the
moon and the pointing of her horns, never for a
moment accepted by those whose reason demands an ad~quate cause for every effect.
But weather proverbs of that other classthose that do have more or less to support
them-are worthy of very careful consideration
and study, for they embody accurate descriptions of phenomena and express the usual
sequence of events.
It can be argued, of course, and with much
show of good reason, that, no matter what its
scientific interest, such a study cannot now have
any practical use, since nearly every country
has a national weather service, whose forecasts,
for any given time and place, are reliably based
upon the known immediately previous conditions all pver a continent, conditions that are
continuously and accurately recorded and carefully studied.
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WEATHER
PROV~RBS
It is true that when one is supplied -with ~uch
information his meteorological horizon IS w(}rldwide. Seeing the weather as it is everywhere,
he knows in what directions tHe storms are
moving, and how fast, hence he can predict
the approximate weather conditions at any
given place a day or more in advance of their
occurrence. But, in general, it is not practicable officially to forecast for definite hours, nor
for particular farms and villages. These very
local and short-range forecasts, though often
of great importance, must, then, be made by
everyone for himself according to his own in.terpretation of the weather signs before him.
Besides.. in many places it is impossible to get,
in time for use, either the official forecast, or the
weather map upon which one may base his own
opmlOns. Under these widespread and Il:lore
or less common conditions certain signs of fair
and foul Clearly are of especial value-signs
which everyone uses to a greater or less extent,
but with an understanding of their signific<uice
that varies from the vague and indefinite, on the
part of those to whom changes of the weather
are of little importance, to the well-nigh full
and complete, by those whose experienc(~ in
watching weather indications has been long and
compelling.
WEATHER PROVERBS
7
Thus, the fisherman today, as in the past,
often weighs anchor and flees from the gathering
storm when the inexperienced would sail on in
blissful expeGtation of continued fine weather;
and the woodsman, as did his remotest ancestors, will note significant changes and understand their warning messages when the average
person would see no change at all, or, if he did,
at least fail to comprehend its meaning.
The prescience of these men is remarkable,
·and it is with some of the useful weather proverbs they know so well, the causes of the
phenomena they describe, and the relation of
these phenomena to others they precede, that
the first part of this book is concerned.
It would be exceedingly profitable if infallible
rules could be given for forecasting the weather,
by signs or otherwise, but, fortunately for our
interest and excitement in the matter, there are
no such prosaic guides. There.-are, however,
two companion proverbs that the sign-forecaster should never forget, namely; "All signs
fail in dry weather," and, "In wet weather it
rains without half trying." Of course, because
when the air is comparatively dry the rainmaking process clearly must be vigorous, and
w hen already nearly saturated, only moderate, to
induce precipitation.
8
WEATHER PROVERBS
}
to
"John, when is it going
rain?" was asked,
during a certain drought, of one known to be
weather-wise. "Well, sir, I just tel1 you, it's
not going to rain till the ground gets wet, then
we shall have plenty of it." Not bad! Because, although the detail of how the ground
was to get wet before it rained was overlooked,
there is full recognition of the important fact
that, in great measure, the weather goes by
spells, each type tending to persist, just as
implied by the above proverbs.
SEASONS
"A good year is always welcome."
Naturally everyone asks: "How will the coming season be?" for much concerning the manner
of our living, and what we may do, depends upon
its type. To the farmer, especially, this is a
vastly important question. A correct answer
to it would tell him what crops to plant and
where; whether upon hill or lowland, as much or
little rain would determine; in light or heavy
soil, for the same reason; and how best to cultivate them, plow deep or mulch, for instancevital points, everyone, to his success. But
whatever we may hope ultimately to accomplish
~
WEATHER PROVERBS
•
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in seasonal forecast~g, it, today, is beyond the
pale of scientific meteorology. Proverb meteorology, however, is full of it, and a few of the
sayings that. forecast the results of a given
kind of season, rather than the type of a coming
one, are rationally founded.
Among them we have:
"Frost year,
Fruit year."
"Year of snow,
Fruit will grow."
Or, in another form,
"A year of snow, a year of-plenty."
That these and similar statements commonly
are true is evident from the fact that a continuous, or nearly continuous, covering of snow,
incident to a cold winter, not only delays the
blossoming of fruit trees until after killing
frosts are probable, but also prevents that
alternate thawing and freezing so ruinous to
wheat and other winter grains. In short, as two
other proverbs put it,
"A cold April
The barn will fill."
"A late spring never deceives."
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WEATHER PROVERBS
o
A different class of proverbs, but one meaning
practically the same thing as the foregoing, and
justified by the same fact, that is, that an unseasonably early growth of vegetation is likely
to be injured by later freezes, is illustrated by
the following examples:
"January warm the Lord have mercy!"
"If you see grass in January,
Lock your grain in your granary."
"January blossoms fill no man's cellar."
"January wet, no wine you
g~t."
"January and February,
Do fill or empty the granary."
"All the months of the year
Curse a fair Februeer."
"A February spring
Is worth nothing."
"March damp and warm
Does farmer much harm."
Another interesting proverb belongin~ to this
class, but requiring special explanation, is:
"Thunder in March betokeneth a fruitful year."
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WEAJHER PROVERBS
Since a: thunderstorm seldom occurs in the
early spring except when a cold wave follows
and breaks up a spell of mild weather (the cold
air overrunning the warmer here and there, or,
at least, walling up against it, and thereby inducing that vigorous uprush of the atmosphere
essential to the thunderstorm) it follows that
thunder in March implies cold weather to follow,
and hence the prevention of the threatened too
early appearance of vegetation.
There are still many other proverbs, perhaps hundreds, that give seasonal forecasts, but,
except those that belong to the above classes,
they have very little worth. Nearly, "if not
quite all, that pretend to foretell the weather
of the coming season range from the purely
fanciful to the utterly inane.
SUN
"Above the rest, the sun who never lies
Foretells the change of weather in the skies."
-VIRGIL.
'While the proverbs
in the most part, are
sands of fancy and of
not all, of those that
concerning the seasons,
built upon the shifting
superstition, many, but
concern the immediate
"
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WEATHER
PROV~RBS
future-the next few hours, or, at most, the
coming day or two-are built upon the sure
foundation of accurate observation and correct
reasoning. Among these perhaps' the best are
those that have to do with the color of the sky
and the appearances of the sun, the moon, and
the stars, for we see the first because of our
atmosphere, and the others through it. The
look, as we say, therefore, of these things shows
clearly the state of the atmosphere, and to the
fisherman, and others of experienced judgment,
is an excellent sign of the coming weather.
Thus, when the air is humid and the sky
growing gray, the c<tnditions, that frequently
precede a gathering storm, then, as Shakespeare
puts it,
"The sun sets weeping in the lowly west,
Witnessing storms to come, woe and unrest."
Of course the condition of the atmosphere
that produces this effect may occur at any hour,
but the consequent modified appearance of the
sun is most conspicuous only when it is seen
through a great thickness of the air, that is,
when it is near the horizon. Hence most
weather proverbs based on the appearance of
the sun refer to morning or evening. Some,
however, are quite general and refer to any
tiVle of the day, as, for instance, the following
WE4THER PROVERBS
13
one with· which we have all been familiar from
childho0d:
«~
red sun has water in his eye."
Now, the condition that most favors a red
sun is a large quantity of dust-smoke particles
are particularly effective-in a damp atmosphere. Smoke alone, in considerable amount
pr0duces this effect, as evidenced by forest
fires during droughts when, of course, it has
no weather significance. The red, however, is
always deepened by the presence of moisture.
The blue and other short wave-length colors,
as we call them, of sunlight are both scattered
and absorbed to a much greater extent by a
given amount of dust or other substances, such
as water vapor, than is the red; and this effect,
since it is proportional to the number of the
particles and to the square of the volume of
each (assuming all to be the same size), becomes more pronounced as the particles unite.
Suppose, for instance, that all the particles unite,
in pairs, or groups of two each. The number
of scattering and absorbing centers will then
be reduced to half the original number, but
each, owing to its increased volume, will be four
times as effective as a single particle. Hence
the net result of the assumed coalescence would
be double the absorption and scattering of the
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PROV~RBS
light. When, therefore, the air is heavily
charged with dust particles that have· becolhe
laden with moisture, as they do in a humid
atmosphere, and hence relatively bulky, we see·
the sun as a fiery red ball.
Clearly, then, a red sun often implies a humid
atmosphere, a condition obviously both essential and favorable to the occurrence of rain.
It is this fact that justifies, in general, the proverb that is under consideration,
and also that .
...
other one that says:
"If red the sun begin his race
Be sure the rain will fall apace."
THE GREEN RAY
"Let us go and see the green ray."
Such was the prompt decision of Helena's
uncles, as told by Jules Verne in his delightful
Scotch story, "The Green Ray," when she
peremptorily refused to marry anyone until
she had seen the green ray-the ray that, according to Highland legend, once seen, prevents
all deception in love, through the magical power
it gives of seeing clearly into one's own heart
and into the hearts of others.
WEAiI'HER PROVERBS
15
But what is the green ray? It is the green
flash, startlingly sudden and brilliant, of the
last speck of the sun as it sinks in cloudless and
exceptionally' clear air below a distant sharply
defined horizon. All the light from the sun,
or other celestial object, is bent down a little
towards the perpendicular as it passes through
the atmosphere; the red portion least of all,
the orange next, then the yellow, green, blue,
and violet. Hence, if the air were perfectly
transparent, which it never is, the last tip of
the setting sun would lose first the red portion
of its light, then the yellow, and so on through
the rest of the pure or spectrum colors, and
finally disappear as a violet star, all in the
course of only a few seconds. The rising sun
obviously would first appear as a violet star,
and then gain additional colors in the reverse
order to the above, and quickly become dazzlingly white.
But, as stated, the air never is fully transparent, but always too turbid to let through
from a low .sun much of either the blue or the
violet light, the colors most enfeebled by transmission through the atmosphere; hence the
violet ray, or flash, is unknown. Indeed the
air usually is so turbid, so laden with dust and
moisture, that the disappearing sun, even to
the last speck, is reddish, the color least affected.
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WEATHER
PROV~RBS
However, when the aIr is especially clear, and
rain therefore improbable for fully twenty-four
hours, much green light also comes through from
the setting sun, and a close observer may easily
see the green ray, especially if so situated that
he may watch for it over a water horizon.
The green ray then, or green flash, whatever
its I!otency in respect to fair women, is at least
a harbinger of fair weather. In proverb form:
Glimpse you e'er the green ray,
Count the morrow a fine day.
SKY COLORS
"Men judge by the complexion of the sky
The state and inclination of the day."
-SHAKESPEARE.
There are many proverbs, ranging from the
good and useful to the misleading and absurd,
concerning the color of the sky at sunrise and
sunset, the times when sky colors are most
pronounced, varied, and significant.
From Shakespeare we have the well-known
lines:
"A red morn that ever yet betokened
Wreck to the seaman, tempest to the field,
Sorrow to shepherds, woe unto the birds,
Gusts and foul flaws to herdsmen and to herds."
WEhTHER PROVERBS
17
Besides these stately verses there are many
proverb· jingles that show substantiaHy the
same weather wisdom. One of them puts it
thus:
"Sky red in the morning
Is a sailor's sure warning;
Sky red at night
Is the sailor's delight."
But in many ways the most interesting of
all the proverbs that have to do with red sunrise and red sunset is the one which, according
to Matthew, Christ used in answer to the
Pharisees and Sadducees when they asked that
He would show them a sign from heaven:
"He answered and said unto them, When it is evening,
ye say, It will be fair weather: for the sky is red.
"And in the morning, It will be foul weather to-day: for
the sky is red and lowring."
It would seem, too, that Christ sanctioned these
views, for it does not appear reasonable that
He would teach by illustrations which He knew
to be false. Then, too, He follows the above
with these words:
"0 ye llypocrites, ye can discern the face of the sky; but
can ye not discern the signs of the times?"
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WEATHER PROVIiRBS
But whether or not Christ accepted these
sayings as reasonably good weather preaictions,
it is certain that those to whom He spoke both
knew them and believed in them .• It is worth
while, therefore, to search, even though the
search be a somewhat tedious one, for the
physical explanation of these phenomena, and
to see how it is possible, if it really is, for identically the same colors of the sky to have one
meaning in the evening and another in the.
mornmg.
To clear the way for this explanation it is
necessary, first, to tell something of the composition of sunlight, and a little about the
atmosphere through which this light passes on
its way to the surface of the earth.
We know that raindrops are colorless, and
we know, too, that when we are between a
falling shower and the bright sun, out of these
very drops comes every exquisite color of the
rainbow. We are also aware that prism-shaped,
colorless, and transparent objects on receiving,
in proper position, a ray of white sunlight emit,
from another face, the rainbow's many brilliant
hues, from the faintest violet to deepest ruby;
and that when all these colored lights are recom-'
bined, or superimposed, the result is white
light again like the original. From such experim'ents and observations we infer that sunlight
WEATHER
PROVERBS
.)
19
is composed, in part at least, of all pure colors,
and that they grade imperceptibly from one
to another.
Furthermore, it is possible to obtain, in ways
that every good work on optics minutely explains, two sources of light, of the same color
and intensity, such that at certain places, fully
exposed to each, they together give illumination more than twice-in fact up to fourfoldfis intense as that from either source alone,
and at closely adjacent places illumination less
than that from but one, even to utter darkness.
Now, this tells us that in some respects light
radiation is like water waves, for two trains of
these may, as nearly everyone has often seen,
so combine as to produce exceptionally large
waves in some places (where the ups of each
come together) and practically smooth water
at others (where the ups of the one are added to
the downs of the other). Indeed, it has been
shown by numerous experiments that light has
several properties identical with those of water
waves. One of these is wave-length, that is,
the distance from a point in one wave or disturbance to the closest corresponding point in
its nearest neighbor, such as the shortest distance from crest to crest or trough to trough.
Of all colors, violet has the shortest wavelength, and red the longest. Blue is next to
20
WEATHER
.
PROV~RBS
violet, yellow next to red, and green about an
average of all. These five are the only colors, and
this their order, that the normal eye naturally
recognizes in the rain bow or other solar spectrum. If the classic (mystic might also be
added) seven are insisted on, then we must
place orange, which few, perhaps, instinctively
regard as a unique color, between red and yellow,
and indigo, which the unguided novice never
singles out, between blue and violet. The.
wave-length of red light is nearly twice that of
violet, and yet it would take more than 30,000
of the longest waves to which the eye is sensitive to span a single inch.
Turning, now, our attention to the atmosphere, we find that at all times the whole of it
is literally teeming with dust particles that
come from fires, dead plants, dry earth, spray
from the ocean, volcanic explosions, and even
the millions of meteors and cosmic motes caught
up daily in our ceaseless whirl and rush through
stellar spa~e. Much of this dust is excessively
fine and can hardly be said to fall out of the
air at all, except as nuclei about which raindrops and snow crystals have condensed.
Besides furnishing the surfaces on. which
condensation can and does start, and thereby
making possible the formation of clouds, the
fall of snow and the comihg of rain, dust pro-
WEATHER
PROVERBS
,
21
foundly affects every beam of light that passes
through. the atmosphere. Thus, as the late
Lord Rayleigh showed long ago, dust motes
and even air molecules, scatter and thereby
weaken a beam of light rapidly more and more
with decrease of wave-length, in fact at a rate
that is inversely proportional to the fourth
power of the wave-length. Hence the scattering
and weakening of violet light, as it passes through
the atmosphere, is tenfold, roughly, blue sixfold, green fourfold, and yellow twice, that of
red.
Furthermore, this scattering and weakening
of the light increases for all colors directly with
the dustiness, or number of dust particles per
unit volume; and also increases with the square
of the size (volume occupied) of the scattering
particle. That is, if the number of dust· particles passed by be doubled, the scattering or
weakening of the light will also' be doubled;
and if the linear dimensions of a particle (diameter, say, if the particle is spherical) be doubled,
or volume made eightfold, the scattering will
be sixty-four times as great.
All this applies to only the very fine dust.
The coarser particles, on the other hand, affect
the incident light both by reflection and by
absorption, but while this effectively decreases
the intensity, it decreases all colors nearLy
22
WEATHER PROVeRBS
equally and thus leaves the quality of the light
roughly the same.
The full mathematical equations that express
the intensity of the light as received at the surface of the earth are a little more complex than
one might infer from the above considerations.
These additional factors, however, will not be
discussed, since enough has already been given
to account for the colors of the sky, the phenomena under discussion, because sky light i~
only the residual reaching us, after all its losses
en route, of that portion of the sunlight which
was scattered by the air and the substances
floating in it. Of course some of the light
reaching the observer has been scattered more
than once, but while this slightly increases the
brightness of the sky it does not appreciably
alter its colors.
It is possible now, keeping the above facts in
mind, to draw some important conclusions.
Thus, since the shortest wave-length light is so
strongly scattered that very little of it can get
through the atmosphere to the surface of the
earth the color of the clear sky, as seen anywhere, except from great elevations, cannot be
violet. Neither can the normal sky be red,
because relatively little of this long wave-length
color is scattered at all. Much violet indeed
starts towards the observer, as likewise in all
WEATHER PROVERBS
23
other directions, from the atmosphere along
the line. of sight towards any portion of the
sky, but very little of it reaches him. On the
other hand, a much larger fraction of the red
gets through, but the original amount is small.
Hence the controlling intensity of sky light
commonly has some intermediate color, generally
blue.
But, as the dominant color of the sky depends
on the relative intensities of the several colors
as they reach the observer, and these compara-'
tive values on the amount of scattering to which
each color is subjected, and this in tum on the
size and number of dust particles in the atmosphere, it follows that different parts of the sky
at the same time, and the same part at different
times, will have different colors depending on
the amount, aggregation, and distribution of
atmospheric dust.
When the dust particles are relatively few
and small the dominant color of the sky is
blue. On the other hand, when the dust motes
increase in size and number, as they do on many
occasions-on dry windy days for instanceor in size only, as happens when the atmosphere
becomes moist, owing to their tendency to
absorb moisture, light of the shorter wavelengths ,is still more enfeebled and the sky
assumes some longer wave-length color, such
24
..
WEATHER PROVERBS
as green, yellow, or even red. Finally, when
the particles are large enough to refleet radiation of all colors, the sky is whitish. Hence
both the morning and the evel'ling twilight
sky often show a series of colors ranging from
red, near the horizon, through orange and
yellow to a green or even blue-green with increase of elevation and consequent decrease in
the number and size of dust particles along the
path of light from the sun to that part of the.
sky in question and thence to the observer.
When the sky is covered with a rather thick
layer of cloud it is, as everyone knows, almost
uniformly gray. This is because the water
droplets that form a cloud, though so small
that a thousand of them would make a row only
an inch long, are large enough to reflect, as do
mirrors, and to refract, or transmit in a new
direction, light of every color. Hence the light
that gets through a cloud layer is the same in
quality, white, as that which falls on its upper
surface.
It remains, now, in preparing the way to an
understanding of the weather significance of
morning and evening colors, briefly to. outline
the essential conditions and processes by which
cloud is formed and rain produced.
Probably that one of these conditions with
w.hich the general public is least familiar is the
WEATHER PROVERBS
25
presence, . In large numbers, of some sort of
nuclei about which water vapor can condense.
In the open air these nuclei are always dust
particles, and, apparently, the molecules or
other aggregates, generally in negligible amounts,
of certain hygroscopic gases or vapors. The
extreme conditions that induce condensation
in the absence of such nuclei, and which may be
obtained in a laboratory, never occur in Nature .
. But besides the presence of dust particles, a
certain relation between the temperature and
the water content of the atmosphere is also
essential to condensation. We say: The warmer
the air, so long as its temperature is below the
boiling point, the greater, and increasingly
greater, the amount of water vapor it can contain in the form of an invisible gas. But this
convenient way of talking about the water
vapor in the air is not strictly correct, for the
atmosphere does not soak up and hold water
like a sponge. In fact the amount of water
vapor that can exist in a given volume is practically not affected at all by the presence or absence of the atmosphere or other gases, but only
by the temperature. Strictly, then, we should
say: The higher the temperature the greater
the amount of invisible water vapor a given
volume can contain. However, it is convenient
to speak of the atmosphere as holding wator
26
WEATHER
PROV~RBS
vapor, and this convenience is allowable provided we do not mean exactly what we" say and
are reasonably certain others will understand
what we do mean.
If, then, air, which always is dusty, containing, as we say, all or nearly all the water vapor
it can hold, is cooled to a distinctly lower temperature a corresponding amount of condensation will take place on each dust mote, and the
countless droplets thus formed will appear as a
fog or a cloud of greater or less density.
The most efficient method of producing the
cooling necessary to cloud formation is to move
the moist air to a place of less pressure, that i~,
lift it up to a greater elevation, where it will
expand and thereby do work against the· surrounding decreased pressure at the expense of
the heat energy it contains. This effect is well
illustrated by the formation of cumuli, or
thunderstorm clouds, in the summer time, the
process of which, in general, is as follows; The
earth is heated by sunshine. The warmed earth
in turn heats the adjacent atmosphere which,
consequently, expands and thereby becomes
lighter, volume for volume, than the surrounding cooler air. The relatively light, warm air,
often nearly saturated with water vapor evaporated from growing vegetation, moist earth,
lakes, and other sources, and by this vapor
WEAlHER PROVERBS
27
rendered. still lighter, is buoyed up by the
cooler aad denser adjacent air, very much as a
cork ,is made to bob up when set free under
water. The lifted, or, as we commonly say, the
rising air, sustains at any particular time only
the weight of the atmosphere that is above it at
that moment, hence, so long as the air is rising
this weight is growing less and as it passes from
a region of greater to one of less pressure it
,expands, just as a compressed spring does when
its load is decreased. As the spring expands, it
must do the work of lifting the remaining weight,
and so it is with the atmosphere-in expanding
it has to lift the air that is still above it and
thereby do work. This work is possible only
because of the heat of the expanding air itself;
hence, as it expands it gets correspondingly
cooler, and, consequently, the amount of transparent water vapor it can contain rapidly
decreases. When the dewpoint (temperature
at which the air is saturated by the moisture
present) is passed, cloud is formed.
A rising mass of air, then, cools because of the
work it does in expanding against the surrounding pressure and thereby soon reaches a temperature, commonly called the dewpoint, below
which it cannot contain as a gas all its water
vapor. Hence any further rising and consequent cooling leads to precipitation-a cpl-
28
WEATHER
PROV~RBS
lection of the excess water vapor a90ut dust
particles--and the formation of cloud .•
·With the foregoing facts clearly in mind it is
easy to understand, in a general way, those
actions of nature that give weather significance
to the sky colors of morning and evening, and,
in large measure justify the proverbs that for
ages have been associated with them. Thus, a
red evening sky means that the temperature
has not fallen below the dewpoint even at th~
tops ,of the strongly-cooled rising currents of
air that are so common during the heated portion of the afternoon (cooling below this critical
point gives a gray or clouded sky owing to
condensation), and hence that the' air contains
so little moisture that rain, within the coming
twenty-four hours, is improbable.
If the evening sky, near tlle western horizon,
is yellow, greenish, or some other short wavelength color, then all the greater is the chance
for clear weather, for these colors indicate even
less incipient condensation (smaller particles,
indicating a greater removal from the ::iewpciint)
and hence a drier air than does red. Clearly,
then, the following lines from Shakespeare
express a general truth:
"The weary sun hath made a golden set,
And by the bright track of his fiery car
Gives token of a goodly day tomorrow,"
WEATHER PROVERBS
29
If, however, the evening sky has none of these
colors, but is overcast with a uniform gray, then
we know that the dust particles have become
loaded with much moisture, even to the development of myriads of water droplets. But this
effect is positive evidence that at considerable
elevations the atmosphere is saturated, a condition that favors rain and justifies the familiar
proverbs:
"If the sun set in gray
The next will be a rainy day."
"If the sun goes pale to bed
'Twill rain tomorrow, it is said."
The above discussion of color phenomena in
relation to the weather applies to the evening
sky only. It remains to explain the origin of
similar morning effects and to point out the
differences in the processes by which they are
brought about.
A gray morning sky means, just as does a
gray evening sky, that at some level the atmosphere is filled with water globules which, as
all such globules do, refract and specularly
reflect light of every color. But the process
by which the morning droplets are formed may
not be, and often is not, the same as that by
which the evening droplets are formed. The
30
WEATHER PROVERBS
"
dust of the day sky is heated by sunshine,
direct or scattered, as are also, to a greater or
less extent, both the air and the earth beneath,
while' the dust in the night sky, at) does everything else that is freely exposed, loses more or
less heat, and thereby cools, through radiation to
space. Besides, the atmosphere during the daytime, and, especially, in the afternoon, is cooled
by expansion incident to rising, and this cooling,
in spite of the counter warming by the sunshine,
often is sufficient to cause more or less conden-·
sation on the dust particles thCj.t are present.
At night, on the other hand, there generally
are but few, if any, rising currents, owing to
the absence of surface heating, and, consequently, no marked expansional cooling of the
air.
Clearly, then, the gray of the morning sky
often may be owing to water droplets that
have gathered as so much dew on the dust particles of the iower atmosphere-dew that has
collected on them because of the slightly lower
temperature they maintain through radiation
to space, just as, and for the same·'reason that,
it collects on blades of grass and other exposed
good radiators. But in order that the marked
radiation, essential to the formation of droplets, may take place, it is necessary that the
atplOsphere above them be dry, for water vapor
WEATHER
PROVERBS
()
31
in quantity does not allow long wave-length, or
air-temperature radiation, freely to pass through
it. Hence a gray morning sky, because it implies
a dry atmoS'phere above the dew droplet haze,
justifies the expectation of a fair day. Even the
droplets to which the gray is due are soon evaporated by the rising sun, nor is any ascension of
the lower humid air likely to cause precipitation
since it is thereby mixed with the much drier
air above.
A red morning sky, however, means several
things quite different from those implied by a
gray one, viz.: That the atmosphere is rather
humid, else the clear sky would have a short
wave-length color, such as yellow or green;
that, as the sky is not gray, there are no dew,
or water, droplets on the dust particles of the
lower air; that therefore this dust has been
protected from excessive loss of heat by radiation; and, from this in turn, that the upper
air contains much moisture, the condition that
holds radiation losses down to a minimum. That
is, a red morning sky implies that the whole atmosphere, up to considerable elevations, is humid,
and rain, therefore, probable, later in the day.
Convection, as we have seen, is largely responsible ;for the colors, the gray especially, of
the evening sky, and radiation for the gray of
the morning sky. Hence the amount and djs-
32
WEATHER PROVERBS
•
tribution of moisture most favorable to any
given sky color, particularly gray m' red, is
radically different in the two cases. There is,
therefore, a real physical basis fO'r, and much
truth in, the proverbs that declare one result to
follow the red sky of the morning, and quite
another that of the evening. Similarly, the
morning and evening implications of certain
other sky colors also differ radically.
Some of the best and most familiar proverbs
of this class are:
"Evening gray and morning red
Make the shepherd hang his head."
"An evening gray and a morning red
Will send the shepherd wet to bed."
"Evening red and morning gray
Two sure signs of one fine day."
"Evening red and morning gray
Help the traveler on his way;
Evening gray and morning red
Bring down rain upon his head."
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WEA,THER PROVERBS
33
RAINBOW
"The bridge of the gods."
-Norse saying.
That glorious photometeor, the rainbow~ap­
pealed compellingly to the imagination of many
primitive peoples. Indeed a book might be
written on its symbolism in religion, and another
on its secular use by the poets of all nations. No
,wonder then that the sailors and the shepherds
also watched and remembered, and soon saw
in the rainbow that which meant so much to
them-a token of the coming weather.
The best of the rainbow's weather signs have
long been formulated in the following proverbs:
"Rainbow at night, shepherd's delight;
Rainbow in morning, shepherds take warning."
"A rainbow in the morning
Is the shepherd's warning;
A rainbow at night
Is the shepherd's delight."
"If there be a rainbow in the eve,
It will rain and leave;
But if there be a rainbow in the morrow
It will neither lend nor borrow."
Perhaps some stickler for truth and accuraCymighty good things to be a stickler for-may
,
34
WEATHER PROV:e;RBS
insist that a rainbow at night is an absurdity.
Well, not necessarily absurd, for occasionally
the moon produces a very pretty rainbow.
However, the word "night," in the first two of
the above proverbs, means evening, in the sense
of late afternoon.
These proverbs have been justified by the
fact that where they originated, and indeed
everywhere in the temperate zones, the prevailing wind, and hence nearly all showers"
including those in which the rainbow is seen,
move from west to east. Clearly, then, as the
argument runs, since .the rainbow is always on
the opposite side of the observer from the sun,
the shower in which an evening rainbow is seen
commonly is moving farther away from the
place of observation and thereby promising
fair weather for that locality, at least so far as
that particular rain is concerned; while, on the
other hand, a morning bow, being seen in the
west, indicates an approaching shower.
All this is good enough, so far as it goes, and
for the immediate neighborhood of the observer,
but the morning and evening bows have a
much broader significance. Since the rainbow
is seen only in local showers (requiring simultaneous rain and sunshine), and since the shower
normally implies a local uprush of the air, due;
afl a rule, to surface heating, it follows that th~
WEATHER PROVERBS
35
general weather significance of the morning and
evening ·bows is essentially the same as that of
morning and evening showers. Now, the surface grows warmer from early morning until
mid-afternoon, unless the sky becomes clouded.
Hence, during this time the air rises higher and
higher, and, owing to the resulting expansion of
this rising air, its temperature and, thereby, its
vapor capacity, become correspondingly less.
Clearly, then, a morning rainbow means
that the air is rather humid, and rains likely, for
a shower has occurred with but little rise of the
air and slight cooling. The evening rainbow,
on the contrary, indicates that the air is comparatively dry, and fair weather probable, for
the existing shower has required the considerable
cooling incident to high ascension.
Another valuable proverb of this class, and
more, perhaps, to the sailor's liking, runs as
follows:
"Rainbow to windward, foul fall the day;
Rainbow to leeward, damp runs away."
The justification of this proverb is obvious.
If the bow is to windward, rain may well be
expected, for the shower is approaching. If the
bow is· to leeward no rain can come from that
shower, at. least, for it is already receding.
Furthermore, since, as above stated, our pre-
•
36
WEATHER PROVPiRBS
vailing winds are from west to east, windward
generally means westward, and leeward eastward. Hence, a rainbow seldom occurs to windward except in the morning, and· therefore it
indicates, as above explained, high humidity
and the probability of showers. Similarly, a
rainbow to leeward is, almost certainly, a rainbow in the evening and therefore, like the latter,
implies that the humidity is low and that the
morrow probably will be fair.
CORONAS AND HALOS
"For I fear a hurricane;
Last night the moon had a golden ring,
And tonight no moon we see."
-LONGFELLOW.
Many proverbs foretelling rain and bad
weather are based on the appearance of solar
aad lunar halos and coronas, and as these very
commonly are associated with the types of
clouds that precede a storm the proverbs of this
class are well founded.
Coronas are the small colored rings of light,
red on the outside, that encircle any bright
object wIken seen through a mist, though the
term commonly is restricted to the colored
,
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WEA1;HER PROVERBS
37
rings around the sun and moon. They are
caused by what the physicist calls diffraction,
that is, the bending of light at the boundary of
an object into its geometric shadow, a phenomenon of the greatest importance in the science
of optics. The angular radius of the corona
depenps on the size of the diffracting objects,
the water droplets, in the sense that the larger
the droplets the smaller the corona. Hence a
qecreasing corona implies growing drops and
the probability of rain. On the other hand an
enlarging corona as definitely shows evaporation
and clearing skies.
Halos, the second of the two classes of optical
phenomena now under consideration, should
not be confused with coronas; and they need
not be, for they consist of arcs and circles of
relatively large diameters. Two, and they by
far the most common, are circular about the
sun, or moon, and have red inner borders.
Three others are circular about the zenith, two
extending only part of the way around, and one
all the way and through the sun itself. Moonlight is too feeble often to render this last halo
visible. The other fifteen or so are variously
scattered over the sky, and though each is
interesting as an optical phenomenon, none has
an individual proverb recognition. The large
circle that passes through the sun, and one C\f
38
WEATHER PROVERBS
two other halos are white, with no tinge of
color, and are caused by reflection by snow
crystals. All the others are more or less colored,
with the red nearest the sun, or moon, except
in one or two very rare halos, and produced by
refraction of the light, or the bending of it out
of its course on its passage through small ice
needles. Halos are very commonly seen in
that high veil of cirrus clouds that so frequently
is caught up from the tops of storms and carried
far ahead by the swiftly moving currents that
nearly always prevail at great altitudes. It is
this usual forward position of halos relative
to moving storms that makes them the fairly
good indicators they are of approaching bad
weather. As the proverb puts it,
"The moon with a circle brings water in her beak."
And, as the Zuni Indians say,
"When the sun is in his bouse it will rain soon."
Several others of these proverbs refer to the
apparent diameter of the circle. Thus we have:
"Far burr, near rain."
"The bigger the ring, the nearer the wet."
"When the .beel is far the storm is n'arj
WlaeD the wheel ~ n'ar dae storm is far!'
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WEAT}IER PROVERBS
39
These cannot refer to the corona, which
actually dbes change in angular size, as explained
above, because in that case just the reverse is
true, namely,' the bigger the ring the farther
off the storm. Clearly, then, they apply only
to the halo. Now, as the apparent size of an
object of constant diameter (the angular diameter of the halo is always the same) depends
upon its seeming distance away, it follows that
the supposed changes referred to are only
optical illusions, due to erroneous impressions
of distance.
A good illustration of this kind of illusion is
furnished by the moon as seen by different
people,) or 3;S seen at different elevations
above the horizon by the same person. \Vhen
high in the heavens, where it appears to be
comparatively near, it looks smaller than it
does when close to the horizon where it seems
to be farther away; and yet careful measurements
show but little change in its angular diameter,
and that little just the reverse of appearances.
Hence, when the actual distance to a halo is
less than it seems to be, as often happens when
the clouds are low, it appears to be unusually
large; and, conversely, when the clouds are
very high a halo in them, because the distance
to it commonly is underestimated, impresses
one as being correspondingly small.
40
WEATHER PRO';IERBS
Now, the higher the cIoud~ the swifter the
winds that carry them along and the farther
removed they become from the parent storm.
Hence, a halo that appears small is due to
clouds that probably are far removed from the
storm that produced them, while a halo that
seems large, since it is caused by relatively low
and, therefore, slow~moving clouds, usually indicates that the storm, if ther~ be one, is comparatively near.
MOON
"But chiefly look to Cynthia's varying face;
There surest signs of coming weather trace."
-ARATUS,
Many people have imagined, indeed many
still imagine, that the moon appreciably controls the weather, and numerous proverbs are
based on this assumed relation. Careful studies
of the records, however, have shown that the
moon's influence on the weather, beyond a
very small tidal effect on the atmosphere, as
indicated by the barometer, is entirely negligible. As has been well said:
WEAT,HER PROVERBS
41
"The moon and the weather
May change together;
But change of the moon
• Does not change the weather.
If we'd no moon at all,
And that may seem strange,
We still should have weather
That's subject to change."
However, the appearance of the mo(Jn de-,
pends upon the conditions of the atmo~phere,
bence proverbs based upon phenomena of this
nature are well founded and valuable. Thus:
"Clear moon,
Frost soon."
"Moonlit nig,hts have the heaviest frosts."
and others of this class, are true enough, because on the clearest nights the cooling of the
earth's surface by radiation is greatest and therefore most likely to cause, through the resulting
low temperature, condensation in' the form of
dew or frost.
The following moon proverbs also have stood
the tests of ages:
"Pale moon doth rain,
Red moon doth blow,
White moon doth neither rain nor snow."
"If the moon show a silver shield,
Be not afraid to reap your field;
But if she rises haloed round;
Soon we'll tread on deluged ground."
42
WEATHER PRO\)ERBS
Here "pale moon" and moon "haloed round"
both imply thin clouds, such as run ahead of a
general rainstorm; "red moon" frequently
implies much humidity, a condition also common for many hours previous to the onset of a
storm; while "white moon," and moon with a
"silver shield," evidence the absence of clouds
and a comparatively dry atmosphere.
One of the most interesting of the moon
proverbs is this:
"Sharp horns do threaten windy weather!'
The bad seeing of the moon and stars, that is,
the fuzzy outlines of the one and the excessive
twinkling of the others, when the air is clear,
is due to temperature inequalities in the atmosphere. These inequalities are greatly decreased,
if not entirely eliminated, by the mixing caused
by strong winds. When the moon's horns, then,
appear sharp these· inequalities do not exist,
and the natural inference is that there are
strong overhead whids which later may reach
the surface of the earth.
The following are, perhaps, the most striking
of all the moon proverbs; apparently silly, both
of them, and yet ripe in wisdom:
"The full moon eats clouds."
"The moon grows fat on ,clouds."
WEATHER PROVERBS
43
A lay~r of rather high and more or less detached ,clouds, looking somewhat like a flow of
ice cakes, is a very common afternoon phenomenon, espeGially during the summer. Now,
as soon as the sun goes down, these clouds, which
are good radiators of heat, grow colder and
cool in turn the air in which they float. This
cooled and, consequently, denser air falls (because of its increased density), dragging the
clouds with it, to lower levels where it comes
. to rest in equilibrium with the newly adjacent
atmosphere. But the lower air is warmer than
the upper, and so it happens that when the
chilled air has come to rest it is warmer than it
was before it was first cooled. That is, the
clouds are thus brought into air that is relatively warm and dry; hence, a layer of afternoon clouds often disappears early in the evenmg.
Now, although the evaporaj:ion of falling
clouds of this type is as likely and frequent
during one lunar phase as another, their disappearance clearly is conspicuous only when
the moon is above the horizon. Hence the clearing of evening clouds from the sky, naturally,
though erroneously, is popularly attributed to
the moon.
Perhaps the idea that the "moon grows fat
on clouds" may have had its origin in the fact
44
WEATHER PROVE;_RBS
that the moon is above the horizon thr.ough the
early portion of the evening, when the cloud
disappearance in question occurs, only duri~g
the first and second quarters, or· while it is
nightly growing fuller and rounder.
STARS
"The prudent mariner oft marks afar
The coming of tempests by Bootes's star.
-AAATUS •
. The stars, like the sun and the moon, have
furnished many proverbs concerning the weather.
Most of the star proverbs, like all others, are
mere nonsense, but a few of them have decided
merit, as, for instance:
"When the stars begin to huddle,
The earth will soon become a puddle."
This proverb furnishes, in general, a cowect
forecast. It also furnishes a curious illustration of the ignorance that once was-perhaps it
would not be far wrong to say still is-so prevalent concerning the stars.
When a mist, due to the beglhning of condensation, forms over the sky, as it does on the
forward side of a storm, the smaller stars cease
WEATJIER PROVERBS
4S
to be visible, while the brighter ones shine dimly
with a blJlr (really a faint aureole and corona)
of light about them, each looking like a small
confused clus~er of stars. Hence the erroneous
idea, implied in the above proverb, that stars
huddle together at one time-just before a rainand scatter about at another. Or, possibly,
huddle, in this case implies hide, an obsolete
meaning, for it commonly is true, as just exJ:!lained, that
When the stars begin to hide,
Soon the rain will betide.
This same idea that fading stars indicate rain,
which of course they do, since they show increasing humidity and haze, was sung ages ago
by the Greek poet Aratus, who put into verse
all the then-known weather wisdom. He says,
in the English of J. Lamb:
"When the bright gems that night's black vault adorn
But faintly shine-of half their radiance shornAnd not by cloud obscured or dimmed to sight
By the fine silvery veil of Cynthia's light,
But of themselves appear to faint away,
They warning give of a tempestuous day."
There is also some ground for the proverb
that declares the number of stars within a lunar
halo to be the number of days before a storm,
46
WEATHER PROVERBS
~
for the nearer the storm the denser t.he condensation, and, of course, the fewer the _!)tars seen
through it. However, as even one entire day
is a pretty long period to cover. by sign forecasting, it would be better simply to say that
the fewer the stars the nearer the rain; though
even in this form it is not very trustworthy
owing to the fact that the brighter stars are
unevenly distributed over the sky.
An entirely different star phenomenon that
has given rise to a few proverbs is twinkling, or
the rapid irregularities itt star brightness. This
fluctuation in their light is caused, mainly, by
irregular refraction due to numerous inequalities
in the distribution of temperature and humidity,
such as necessarily accompany the over and
under running of air currents of different origins,
a condition that often precedes a storm. ~ence
. the justification of the prosaic proverb that
says:
"When stars flicker in a dark background rain or snow
follows soon."
.'
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WEAlHER PROVERBS
47
FOGS
"He thaI would have a bad day mawn gang out in a fog
after a frost."-Scottish saying .
.
Although fogs have furnished only a small
part of our traditional weather lore, nevertheless
~hey have inspired a few sayings which, like the
one above, are worth remembering.
The cause of fog is the cooling of the surface
air to " temperature below its dewpoint, that
IS, the temperature at which the air is fully
saturated by the water vapor present. This
decrease in temperature may be caused in several
ways.
If the skies are clear the surface of the earth
loses much heat· by radiation to space, and if,
at the same time, there is no wind the atmosphere near the ground often becomes so chilled
as to condense some of its vapor onto the myriad
millions of dust particles always present, thereby
producing fog. This phenomenon is particularly frequent, from midsummer to early autumn
along valleys and wherever else on land the
lower air is humid and so hedged about that
it can not flow away as fast as cooled.
Of course there are clear still nights during
the winter too, but radiation fogs, as this kind
is called, are far more prevalent in the summer
time, because the amount of moisture in the
48
WEATHER PROVERBS
air, along streams at least, and also the extent
of its cooling (number of degrees losty. through
the night are much greater then than during
the colder season.
Another frequent cause of fogs is the flow of
humid air over relatively cold surfaces, such as
the drifting of on-shore winds over snmv banks;
and, during winter, the travel of the rain-carrying, southerly currents to more northerly points
across plains and hills of increasing cold.
Clearly, then, one might say, in proverb
form:
A summer fog for fair,
A winter fog for rain;
A fact most everywhere,
In valley and on plain.
Obviously, too, whenever the atmosphere
beyond a few hundred feet above the earth is
comparatively dry a radiation fog is soon cleared
away by the warmth of the sunshine and the
convective or overturn mixing of the surface
and upper layers of air that always occurs on
still clear mornings. If, on the contrary, the
free air is quite humid through a considerable
depth the fog may not evaporate on rising, but
hang on hill and mountain tops, merged with
a growing cloud that soon brings rain. Hence
the proverb:
FRACTO-STRATUS, ScUD, :MIST.
"When the mist creeps up the hill."
~ :HER
PROVERBS
•
49
"Mists dispersing on the plain
catter away the clouds and rain;
ut when they rise to the mountain tops
The~ soon descend in copious drops."
When a general rain is coming on it often
happens that hills and mountains become cloudcapped, and that on the lee sides portions of
these clouds are drawn out as scud and dragged
to lower levels, where, as a rule, they evaporate.
On the other hand, the ending of these storms
commonly is accompanied by the onset of
cooler, drier, winds from a different direction
that drive up the mountains and clear away all
remaining fogs and low-lying clouds. In other
words:
When fog goes up the rain is o'er,
When fog comes down '~ rain some more.
Or, as the familiar proverb puts it:
"When the mist creeps up the hill,
Fisher, out and try your skill;
When the mist begins to nod,
Fisher, then put by your rod."
50
WEATHER PROVltRBS
CLOUDS
"And now the mists from earth are clouds m eaven."
-WnsON.
The height, extent and shapes of clouds depend upon the humidity, the temperature, and
the motion of the atmosphere; hence they often
give reliable warnings of the coming weather.
As is well known, clouds are formed mainly
by cooling due to ascension of the lower humid.
air. The rising air comes under less and less
pressure by the weight of the atmosphere left
below, hence it as continuously expands against
the weight of the air still above, and does this
work at the expense of its own heat. High
clouds, therefore, having required much cooling
to form, obviously do not contain enough
humidity to produce any considerable rain or
snow. In short, with respect to all cloud forms
of the cumulus or wool pack type, at least:
"The higher the clouds, the finer the weather."
This proverb does not apply to the thin,
wispy, cirrus clouds, the highest of all, that
float from five to eight miles above sea-Jewel.
Part of the air that forms the upward currents
in the forward portion of a general or cyclonic
storm rises to great heights where, in middle
latitudes, it gets into the swift, eastward-moving,
'I
CUMULUS .
(E. E. fiAR"SAlm, PHoTO.)
"And now the mists from earth are clouds in heaven."
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THER PROVERBS
S1
..t; ...
da 'that carry it and its ice particles far
okhe..rains. There also are other ways
hich this kind of cloud is formed, but since
theway just plained is very common, and the
only the forerunner of a
. cirrus thus produ
stonn that is comi in the same general direction, it is evident that the following familiar
proverbs well deserve a place in our memory:
·
E
"Mackerel scales and mares' tails
Make lofty ships carry low sails."
"Trace in the sky the painter's brush,
The winds around you soon will rush."
.I
On the front side of a general stonn the lower
and upper winds run in more or less different
directions. Furthermore, both are humid and
often cloudy. Not infrequently too, the lower
clouds are so broken that the layer above may
also be seen-the two streams rapidly crossing
each other. Hence, if one may coin a needed
"proverb, "
Whene'er the clouds do weave
'Twill storm before they leave.
,
•
On th~ front .ot rainy side of a wide-spread
storm th clouds of the humid winds come lower
and 10
until the rain begins. Now, it often
~appe
that mountain ridges and peaks
ar,
S2
• J.
higher than the base of the rain cloud, ill' whicb,
cases these mountain tops become efeuded a
few hours before the rain begins. This, in ture,
has led to many local sayings in which the
name of some particular mountain is used, as,
for instance:
"When Breedon hill puts on his hat
Ye men of the vale beware of that."
"When Cheviot ye see put on his cap
Of rain ye'II have a wee bit drap."
"When Traprain puts on his hat
The Lothian lads may look to that."
"When Pembroke puts on his cowl,
The Dunion on his hood,
Then a' the wives of Teviotside,
Ken there will be a flood."
"When Falkland Hill puts on his cap,
The Howe 0' Fife will get a drap;
And when the Bishop draws his cowl,
Look out for wind and weather foul."
Although weather proverbs that refer to the
clouding of mountains are peculiarly ~ aapted to
a display of parish pride, nevertheles: a few of
this class, recognizing the fact that ~here are
more m
tains than one, are quite gl.mera1 in
form. two of the best are:
CUJC( "" -)T
SHASTA.
(cr. A. GILCHRIST, PHOTO.)
, f Jmoming mountains, in the evening fountains."
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WEATHER PROVERBS
53
"When the mists begin to nod
Fisher, then put by your rod."
"When the clouds are upon the bills
They'll come down by the mills."
As everyone knows, who has watched the
weather at all closely, small cumulus or woolpack clouds imply fair weather, while a large
cumulus often develops a thunderstorm. These
clouds, as is also well known, are caused by the
rising of air from near the surface to considerable heights and.its consequent cooling, through
expansion, to temperatures below the dewpoint.
If, now, the decrease of temperature with increase,of elevation is such that large cumuli are
formed during the forenoon it is obvious that,
owing to further heating of the surface, ascension of the air, and the resulting clouds, will be
still greater during the afternoon, and that
some of these larger clouds will give rain. Hence
those proverbs are well founded that say:
.
,
''In the morning mountains,
In the evening fountains."
''When the clouds appear like rocks and towers
The earth'. refreabed by frequent showers."
Finally, since the weather varies with, indeed largely depends upon, the direction of the
'"
54
WEATHER PROVERBS
.'
wind, it follows that the "carry," or curre:tt of
the clouds, often is good evidence of the kind
of weather on the way-foul, commonly, if
from the east; fair if from the west. As the
proverb puts it:
"When the carry goes west,
Gude weather is past;
When the carry goes east,
Gude weather comes neist."
RAIN
"When God wills, it rains with any wind."
-Spams" saying.
Whether this Spanish saying is indicative of
exceptional piety, or only disgust over the apparent arbitrariness of the weather, may be
left to the mood and judgment of the reader.
If he happen to be an amateur forecaster,
whether from observation of signs or study of
a weather map, it is certain that freQ'1ently he
will be disposed to accept the second of these
interpretations.
As we have already seen, ~'ld as will appear
in the following pages, there are many good
signs ·of rain, but there are very few weather
55
WEATHER PROVERBS
signs. to be seen in the rain itself.
this is the best:
Perhaps
"Rain long foretold, long last;
Short notice, soon past."
That is, 'if for a day or two the clouds have
slowly extended and thickened it is probable
that the resulting rain will be correspondingly
persistent; but if the clouds have gathered
rapidly there will be only a passing shower.
The first of these processes, the gr~dual increase of cloudiness over a day or two, is
typical of the passage of a cyclonic or widespread storm in which the rain usually lasts
several hours. Hence the justification of the
first portion of the proverb. Similarly, the
rapid gathering of rain clouds indicates quick
action, such as that of a thundershower or a
squall, storms of small extent and, therefore, of
short duration.
Another well-known rain proverb says:
"Sunshine and shower, rain again to-morrow."
Obviouf)ly, "sunshine and shower," generally
implies rain from a cloud of very limited extent,
and rain from so small a cloud implies, in turn,
quite humid air and a distribution of temperature favDrable to local ascenSIOns and overturns. Hence, as such conditions commonly
56
WEATHER PROVERBS
persist from one to several days, sunshin~ and
shower on one day may well be followed by
showers the next day.
DEW AND FROST
"The dews of the evening industriously shun,
They're the tears of the sky for the loss of the sun.',
-EARL OF CHESTERFffiLD .
•
The amount of invisible water vapor a given
space can contain increases rapidly with the
temperature, and decreases just as rapidly
with loss of temperature. A familiar and excellent example of this fact is seen in the "sweating" of the ice-pitcher-deposition of moisture
from the cooled atmosphere onto the sides of
the vessel. This sweating is owing entirely to
the cooling of the adjacent vapor (the presence
of the other gases of the atmosphere does not
affect the result) below the dewpoint, or te~­
perature at which the water vapor present is
just sufficient to produce saturation.) Clearly,
then, for each given amount of moisture in the
air per cubic foot, say, there is a particular
temperatur~ below which all exposed objects,
no matter by what process they hcl,Ve been
cooled, become more or less wet with the con-
WEATHER PROVERBS
57
densa.tion of this moisture onto their surfaces.
Clearly, too, the lower the temperature reached
the greater the amount of water deposited.
Now, every. object is always losing heat by
radiation and, at the same time, gaining heat
by absorption of radiation from surrounding
objects. A good radiator therefore, such as a
growing leaf, loses heat rapidly. If at the same
time it is exposed to a cloudless night sky, and
if there is but little humidity in the atmosphere,
the return radiation that may be absorbed is
comparatively small, for dry air is a very poor
radiator. In this case the leaf, say, cools, unless its temperature is otherwise kept up, until
its enfeebled radiation drops down to equality
with its absorption. One way of keeping up
this temperature is to bring fresh uncooled air
(air of itself does not cool rapidly) in contact
with the radiating object. Thus, if the object
in question is a leaf on a tree the' air in contact
with it trickles down immediately it is slightly
cooled and thereby causes un cooled air to take
its· place and to prevent the leaf from becoming
nearly so ~old as it otherwise would. Similarly,
any appreciable wind stirs up the air through
so great a depth that even grass is prevented
from greatly cooling by the constant supply
of relati-vely uncooled air.
58
WEATHER PROVERBS
Hence, when the air is dry, the .sky ~lear,
and there is no wind, the temperature of the
grass falls many degrees, except on hillsides
where the chilled surface air cal\, drain away.
Usually, too, this chilling is well below the
current saturation temperature, and hence much
dew is deposited. If, however, the sky is
clouded, or if the air is quite humid, there will
be a relatively large amount of return radiation,
for both the clouds and the water vapor are good
radiators, and the grass will not cool very much,
even during the stillest night, nor, therefore,
will much if any dew be deposited.
In short, then, dew forms abundantly only
when the condition of the air is such that rain
can hardly occur; and, on still nights, fails to
appear only when the conditions are such that
rain is probable.
Obviously, all the above- discussion of dew
applies equally to frost, for temperature alone
determines whether the deposit shall be the one
or the other-dew if the temperature is above
the freezing point, frost if it is below the freezing
<}
point.
There is, therefore, ample justification for
the following proverbs:
"Heavy frosts generally are followed by fine clear weather."
WEATHER PROVERBS
59
"When the grass is dry at morning light
Look for rain before the night."
"When the dew is on the grass
Raw will never come to pass."
As these proverbs are particularly helpful, a
briefer version of them is also suggested, since
the shorter forms may be easier to rememJ:ler:
When the morn is dry
The rain is nigh.
When the morn is wet
No rain you get.
WIND
"Every wind has its weather."
-BACON.
The prevailing direction of the wind in
middle latitudes is from west to east, rotlghly.
Winds of any different direction and, especially,
shifting "Winds, imply a storm disturbance of
some kind. For instance, the cyclone, or region
of low atmospheric pressure, is always accompanied by a system of winds directed spirally
inwards. and counterclockwise (in the northern
hemisphere, clockwise in the southern) about the
60
WEATHER PROVERBS
center. Now, this wind system almost invariably
moves eastward, and is nearly always accompanied by precipitation on its front side, and
clearing weather to its rear.
"
Hence, as the storm approaches, the weather
glass (barometer) falls-the pressure of the atmosphere becomes less-and the wind backs,
that is, the direction from which it comes slowly
changes during a few hours in a counterclockwise direction; and as the storm recedes the
barometer rises and the wind veers, as we say,
or comes from a point that shifts clockwise.
The above facts fully justify the proverb
that says,
"When the wind backs and the weather glass falls
Then be on your guard against gales and squalls."
The falling of the pressure, as indicated by
the barometer, or weath~r glass, and the backing
of the wind, are together almost certain evidence
of an approaching cyclonic storm.
"A veering wind, fair weather;
A backing wind, foul weather."
~
As above explained, the wind backs as a
cyclonic storm approac,hes, and veers'\ as it recedes; hence, both portions of this proverb are
fully sustained.
0
WEATHER PROVERBS
~1
"When the smoke goes west,
Gude weather is past;
When the smoke goes east,
Gude'weather comes neist."
•
That is, when the wind is from the east a
storm is close at hand, as already explained, but
is past and gone when the wind gets back from
the west.
"When the wind is in the south,
The rain's in its mouth."
The southeast section of a cyclonic storm,
the section in which the wind is from the south
is, as a rule, a rainy region. Here the winds
are warmest, and, commonly, the most humid; besides, these are the winds that, owing to their
trend, over a considerable area, towards a common point-their convergence-and the presence in front of them of colder, denser air are
forced to rise and thereby produce cloud and
precipitation.
"The wind from the north-east,
Neither good for man nor beast."
This wind obviously is cold, and, being
cauqed, as a rule, by an approaching storm, is
almost certain to bring disagreeable rain or
snow.
"The wind in the west
Suits everyone best."
62
WEATHER PROVERBS
This is because such winds are apt to be
gentle, and seldom accompanied by precipitation.
"Do business with men when the wind is ill the n0:tthwest."
This bit of ancient wisdom is based on the
fact that these winds, being cool, dry, and
bracing, stimulate courage and zest-giv~ "pep"
as the athlete and t'he sportsman would put it.
The following three sayings which have no
relation to the above, nor to each oth.er , are
also worth quoting.
"A high wind prevents frost."
It crIb-a {Treverrt:::> dew~ crad Iur dre- SCfIl"fe' reason,
viz., because it continuously brings frlesh air
to the surface of the earth and thereby Prevents
the cooling of the grass and other such objects
to temperatures below the current dewpoint.
•
"The whispering grove tells of a storm to
com~."
"Nor less I fear from that hoarse, hollow roar
In leafy groves and on the sounding shore."
-LUCAN, Rowe's t~an."lation.
During fair weather the winds are toc) light,
usually, to produce the familiar rustle of Ileaves
and aeolian sighing of twigs and branches.
The "whispering grove" implie;,), considerable
WEATHER PROVERBS
63
wind, and. this, in turn, conditions that: immediately precede and accompany gener;:tl, or
cyclonic, storms.
"The wind.s of the daytime wrestle and fight
Longer and stronger than those of the night."
This is because the lower air, the movernents
of which constitute the winds we experience, is
more mixed with the swifter upper air during
the day when ascension and overturning, incident to surface heating by the sun, is strong,
than it is at night when such overturning, or
vertical convection, is relatively feeble.
BAROMETER
"The hollow winds begin to blow,
The clouds look black, the glass is low."
-DR. 'E. DARWnJ (?).
It would be hard to find a surer sign of rain
than the above, if we except the old Indian sign
our grand... dads used to tell us about-"doudy
all around and pouring down in the middle."
Although the barometer is of the greatest
value as an indicator of the coming weatper it
has inspired but few proverbs. Perhaps this
is the best:
64
WEATHER PROVERBS
"When the glass falls low,
Prepare for a blow;
When it rises high,
Let all your kites fly."
This proverb is based on the fact" that no considerable decrease of atmospheric pressure ever
occurs except in connection with a general
storm; nor markedly high pressure except in
connection with fair weather.
The state and behavior of the barometer is
much more significant, however, when observed
in connection with the winds. Thus a falling
. pressure and backing winds, that is, winds
shifting counterclockwise, as from southwest,
south, southeast, east, etc., together imply
an approaching storm. As the proverb says:
"When the wind backs and the weather glass falls,
Then be on your guard against gales and sqmills."
The various other joint indications of wind
and barometer have not been clothed in proverb
style, but have been assembled, stripped to th~
bone, in concise tables of reference. One of
the fullest and most reliable tables of this
kind was prepared by the late E. B. .tlGarriott,
of the U. S. Weather Bureau, and i~ substantially
as follows. On the whole it is the best weather
guide an isolated observer, provi ded with a
barometer of any kind, mercurial or aner·oid, has
ever had:
n
WEATHER SIGNIFICANCE IN THE UNITED STATES OF BARO:!ol:'LTER AND
WIND DIRECTION
BAROMETER
WIND FROM
WEATHER INDICATED
High aond steady
SWtoNW
High and rising rapidly
SW toNW
High and falling slowly
Very high, falling slowly
SW toNW
SW toNW
High and falling slowly
High and faIling rapidly
S to SE
S to SE
High and falling slowly
High and falling rapidly
SE toNE
SE toNE
High and falling slowly
E to NE
High and falling rapidly
E toNE
Low and falling slowly
SE to NE
Low and falling rapidly
SE to NE
Low and rising slowly
S to SW
Low and falling rapidly
S to SE
Low and falling rapidly
E to N
Fair and little temperature change for one to
two days
Fair followed by warmer
and rain within two
days
Rain in 24 to 36 hours
Fair and slowly rising
temperature for two
days
Rain within 24 hours
Increasing wind with
rain in 12 to 24 hours
Rain in 12 to 18 hours
Increasing wind with
rain in 12 hours
Summer and light winds,
fair; winter, rain in
24 hours
Summer, rain in 12 to
24 hours; winter, rain
or snow with increasing winds .
Rain will continue one
or tW9 days
Rain and high wind;
clearing and cooler in
24 hours
Clearing soon and fair
several days
Severe storm soon, clearing and cooler in 24
hours
Northeast gales with
heavy rain or snow,
followed in winter by
cold wave
Clearing and colder
Low and rising'rapidl}"
,. .
Going to W
" 65.
66
WEATHER PROVERBS
THUNDER
"The winds grow high;
Impending tempests charge the sky;
The lightning flies, the thunder roalS;
And big waves lash the frightened shores."
-PRIoR.
Although thunder is one of the most con- .
spicuous of all weather phenomena it has but
little value as an indicator of coming weather,
and hence has evoked very few proverbs
It occasionally happens that a want· ,pell
of weather in the spring of the year is .~.ken
by squalls and thunderstorms incident (just
how would require too much digression to explain) to the onset of a cold wave. Now this
late cold wave checks the budding of fruit
trees and delays their flowering, and the
putting forth of all tender vegetation, until
after the probable date of the last killing frost.
Clearly, then, the following proverbs are reasonable:
''Thunder in spring
Cold will bring."
"Thunder in March betokeneth a fruitful year."
Thunderstorms, as is well known, are due to
that convection, or upward movement, of humid
air that produces the towering ~ulus cloud.
•
67
WEATHER PROVERBS
Now., this convection commonly IS distinctly
more vigorous over land during the afternoon
than in the morning. Hence, if the conditions
of the atmosphere permit a thunderstorm in
the forenoon they are apt to be even more
favorable to rain in the afternoon. That IS,
as a rule, perhaps,
"When it thunders in the morning it will rain before night."
SOUND
"There is a sound of abundance of rain."
-ELIJAn.
As a general or cyclonic storm approaches, the
sky invariably becomes clouded over and the
air grows more and more humid. The first of
these conditions, that is, the cloudiness, prevents the formation of new inequalities of
density and the setting up of further convection,
while the second aids in the smoothing out of
any temperature differences that previously
may have been present, and which, as Tyndall
showed many years ago, greatly dissipate sound
and limit the distance to which it can be heard.
On the approach of a storm, then, the sounddissipating irregularities of the atmosphere, so
68
WEATHER PROVERBS
common and numerous on clear days, pt;actically all disappear. Hence there is good reason
to accept the proverb that says:
"Sound travelling far and wide
A stormy day will betide."
•
Another herald of the approaching general
storm is the increase of the wind in the upper
levels and its gradual extension to lower and
lower air. Hence, among forested mountains,
especially
"In winter, when the dismal rain
Comes down in slanting lines,
And Wind, that grand old harper, smites
His thunder-harp of pines,"-ALEXANDER SMITH.
when the muffling leaves are gone and the twigs
are free to mingle their myriad aeolian tones,
the coming storm is heralded by the murmuring
of the forest and the roarmg of the mountain.
In proverb form:
When the forest murmurs, and the mountain roars,
Then close your windows and shut your doors.
WEATHER PROVERBS
69
ST. ELMO'S FIRE
"Sometimes I'd divide
And burn in many places; on the topmast,
The yard~ and bowsprit, would I flame distinctly,
Then meet and join."
-SHAKESPEARE.
From the time, perhaps, the first mariner
sailed the seas, and certainly through all the
long years of ancient Greece and Rome, the
Middle Ages, and down to the present, St.
Elmo's fires, those strange heatless flames that
on darkest and dread est nights top the masts
and tip the spars, have been objects of the
sailor's awe and superstition-the souls, some
say, of drowned seamen come to warn their
mates of a pending storm and possible wreck.
But the sailor's storm experience is sounder
than his spiritualistic training! St. Elmo's fires
are not the kindly souls of sailors lost in some
awful tempest, and yet they do often warn of a
coming storm. They are indeed nothing but
electric manifestations due to the highly charged
condition~ incident to thunderstorms, of the
-passing clouds and upper air, a condition that
causes tall objects whether on land or sea
to flare with a continuous coronal or brush discharge. Clearly, then, in the experience of the
mariner~ they are most common on the warmer
70
WEATHER PROVERBS
oceans (actually more frequent still on.moun,tain
peaks) and since they indicate the prevalence of
thunderstorms we may well agree that the following conclusion is in accord with experience
and not, as some would tell us, merely prompted
by superstition:
"Last night I saw Saint Elmo's stars,
With their glittering lanterns all at play,
On the tops of the masts and the tips of the spars,
And I knew we should have foul weather today."
TIDE
"The punctual tide draws up the bay
With ripple of wave and hiss of spray."
-SUSAN COOLIDGE.
The tide indeed is punctual, depending as ~it
does on the positions of the sun and the moon,
and can be predicted, even reeled off with
amazing accuracy by a machine, for years
ahead. Storms, on the other hand, are utterly
irregular~ They come on any day of ,the we.ek
and any hour of the day, without solar, lunar,
planetary, stellar or other control that can
impose upon them even a semblance of punctuality. Nothing is more certain than the times
of the tides, and nothing more uncertain than
WEATHER PROVERBS
71
the pay and the hour of a storm, and yet many
a keenly observant coast man-boatman, fisherman-not only believes, but positively knows,
that:
"Showers are most frequent at the turn of the tide,"
and that
"Storms burst as the tides turn."
And they are right. To them, as to most of
us, the tide is only the flooding and ebbing
of the c~astal water whenever it may occur
and whatever the cause. Now, nearly all storms
including thundershowers, are associated with
changes, especially decreases, in the atmospheric
pressure; and this change of air pressure frequently is the equivalent of more than a foot of
water. Hence, as the local pressure of the
air grows less or greater the level of the ocean
at that place must become cprrespondingly
higher or lower, respectively-as the barometer
goes down the tide must flow; as the barometer
rises the tide must ebb, unless, in each case, the
joint lunar and solar control happens to be in
the opposite sense and more compelling.
In short, the low barometer and the storm
are inseparably associated, and the low air
pressure .leads at once to the inflow of a compensatins weight of water. These irregular
72
w~~rHER
PROVERBS
"tides" are caused by the very condition Jhat
is also the direct cause of the storm. Of course,
then, storms are most frequent with such tides
as these, or, in the words of the multitude, to
whom a tide'is a tide, be the flow when or what
it may, "rain is most frequent at the turn of
the tide."
ODORS
"A very ancient and fish-like smell."
-SHAKESPEARE.
The above quotation describes the kind of
odors that enable some sensitive noses to "smell"
rain. How it all comes about is simple enough.
Decaying organic matter in stagnant ponds and
ditches and undrained fetid swamps produces
much foul gas that accumulates in bubbles
under the mud. Now, the approaching storm
is, as we know, immediately preceded, and
accompanied, by a considerable decrease of the
atmospheric ·pressure. This in turn'lessens the
pressure on the mud-imprisoned bubbles of
putrid gas, allowing them to expand, break
loose, and come to the surface in correspondingly increased numbers, numbers that occasionally render the local atmosphere perceptibly
offensive.
WEATHER PROVERBS
73
1<rom these reasons it is clear that one would
be more or less justified in saying, if he wished,
When the ditch and the pond offend the nose
Then look for rain and stormy blows.
SPRINGS AND WELLS
A rising well and a gushing spring
Are two good signs of the very same thing.
-Nonce jinr)e.
And that same thing is a coming storm, as
many an observer has learned from the beginning of time. The average spring and the
average well respond indeed scarcely at all to
the passing storm, however severe, but there
are others of each that behave in a most remarkable manner. Such wells rise perceptibly
higher, and a few become evert ebullient and
noisy, on the approach of a general rain, while
the sensitive springs flow more freely. Some
springs indeed after having gone entirely dry
•
will start afresh even hours before the rain of
the exciting storm begins. The causes of these
strange phenomena are very simple.
During dry weather the underground water
caverns and channels become more or less
74
WEATHER PROVERBS
drained and filled with air, or other· gas, ,that
has slowly filtered in; leaving, however, the
exit into the well or spring still filled with
water, whether flowing feebly or e.ntirely stagnant. In any such case the entrapped air
within the caverns and crevices is in pressure
equilibrium, through the intervening water,
with the atmosphere outside. Now, a general
storm, as any meteorologist can tell us, is always accompanied by a decided drop in the
atmospheric pressure, and this drop usually
extends far ahead of the rain. Clearly, then,
this decrease in the outside pressure that precedes a general rain allows the entrapped air
to drive, in unwonted volumes, the remaining
underground water into the wells and out of
the springs.
A cavern that happens to be empty, or nearly
so, and near the outlet, will, of course, give off
a stream of bubbles, a fact that explains the
ebullition and noise of some wells on the approach of a storm. If, on the other hand, all
the caverns and crevices are full of water changes
of the outside, or atmospheric, pressti're cannot
affect the height of the well or flow of the spring,
for there are then no entrapped cushions of air
to respond to the external conditions. Hence
the sensitive wells and springs are sensitive only
during the drier seasons.
WEATHER PROVERBS
7S
In" the· cases, then, of our best barometer
wells and occasional predicting springs, fc>r both
of which there should be proverbs, but are not,
we might truthfully say:
Very well we know,
When a well doth well,
A rain and a blow
It doth foretell.
When the spring that's low
Begins to flow;
Then sure, we know,
'Twill rain or snow.
HAIRS, STRINGS, AND OTHER THINGS
"But I know ladies by the score
Whose hair, like seaweed, scents the storrP;
Long, long before it starts to pour
Their locks assume a baneful form."
·-HERBEttT.
A great many substances, both orga(1ic and
inorganic are more or less hygroscopic, That
is, they absorb moisture in proportion to the
dampness or humidity of the atmosppere to
which they are exposed. Now the atmosphere
is comparatively dry, as a rule, duripg fair
weather, but becomes more and more humid
as a general storm approaches. Hence any
76
WEATHER PROVERBS
hygroscopic substance may be used to give
some indication. through its change in length,
size, weight, feel, or other property, of the coming weather. Thus ordinary tabl~ salt grows
heavier and more inclined to pack, cordage
becomes tighter, doors and windows harder
to open and shut, strings of whipcord more
tightly twisted, curly hair more unruly still,
and a thousand other like annoyances more and
more pronounced as the air grows damper and
the storm comes closer. As one might put it,
there being no old, appropriate proverb,
Curls that kink and cords that bind;
Signs of rain and heavy wind.
It was in humorous recognition of this class
of weather signs that The Propheteers, one of
Punch's cleverest poems, was written:
THE ;I'ROPHETEERS*
(With apologies to the Meteorological Office)
In some high mansion, I suppose,
The weather-men confront the stars,
Giving "the glass" tremendous blows
And drinking deep at isobars;
And, though I love the language of their art
And all those little arrows on the chart,
There is a thing that jars.
* Reprinted by the kind permission of the proprietors of
Punch.
WEATHER PROVERBS
,It is the case\that human brain
Can trace the heavenly secrets so,
The cyclones rushing round in Spain
Or bearing down on Pimlico,
And if we'll want our flannels or our furs,
By simply studying barometers- .Can we believe it? No.
But I know ladies by the score
Whose hair, like seaweed, scents the storm;
Long, long before it starts to pour
Their locks assume a baneful form;
Ah, who has not with Muriel rejoiced
One morning when her hair was much less moist,
Meaning it must be warm?
And I believe, with brush and comb,
Some damsel in an inner shrine
Sits always at the prophet's home
While sages all around recline,
Or wait with reverence on the outer mat
Until in ecstasy she pins a plait
And shrieks, "It will be filJ.e."
Then haste they to the great high-priest
And scribble down the mystic rune,
"An anti-cyclone, moving East,
Will stabilise conditions soon;
An inch of sunshine has occurred in Hants;"
Whereat the whole world puts on thinner pants,
And practises the swoon.
77
78
WEATHER PROVERBS
But when they hear the sibyl chant,
"All colourless, and feels like clay,
All straight and horrible- I can't
Do nothing with my hair today!"
Then write they down, "A deep depression runs
South-west from Iceland-secondary ones
Are busy in the Bay."
Think of the powers of that young girl,
And how much destiny must hinge
On whether she can get a curl
To come in her confounded fringe!
Ah, what, I wonder, would the nation do
Suppose one dlJ.y she took a wet shampoo
Or went and had a singe!
And if at times the forecasts sing
Of heat and sun and anticycs
Anr;l we, in fact, get no such thing,
But rain enough to bust the dykes,
Well, even oracles are much like men,
And I suppose that that's what happens when
The Sibyl simply strikes.
-LT.
A. P.
HERBERT,
R.N.V.
SMOKE
"You k'n hide de fier, but w'at you gwine do wid
de smoke?" -JOEL CHANDLER HARRIS.
In this particular case we are going to use
it as a weather sign, just as our ancestors have
done since first they began building fires.
WEATHER PROVERBS
79
Essentially, smoke is only a cloud of fine,
unburned, 'soot, charcoal, or carbon particl~s,
'carried up with the hot air over the fire, together with a small amount of mineral ash.
All. these particles, of whatever nature, becon1e
moisture-laden in a humid atmosphere, such as
commonly precedes a general rain, and slowly
descend. If the air is dry the smoke particles
condense upon themselves little or no moistur"e,
remain light and soon become so scatter~d
through the atmosphere as to be no longer
perceptible. Indeed if the wind is at all strong,
smoke is soon widely scattered and lost, wha.tever the humidity.
When, then, the movement of the wind is
slow, the sky so covered with clouds as to
prevent ascension of the lower air (due to sU.rface heating) and the humidity high (both the
latter usual pre-storm conditions) smoke, after
rising a short distance with the heated air,
drifts away in a rather compact, slowly descending, stream. Hence, often before a rain,
when the conditions are right, and as a sign of
its coming.,
"The smoke from chimneys right ascends,
Then spreading back to earth it bends."
80
WEATHER PROVERBS
PLANTS
"Pimpernel, pimpernel, tell me true
Whether the weather be fine or no."
A similar appeal might, with equally good
reason, be made to the dandelion, the red
clover, the silver maple, and numerous other
plants and trees, all of which commonly undergo
some change, such as the closing of their flowers
or an alteration in the attitude of their leaves,
on the approach of rain. Hence we say:
"When leaves show their under sides,
Be very sure that rain betides."
This hanging of the leaves so as to show their
under sides, when viewed laterally, or at a distance, is owing to changes in the leaf stalk ~n
the absorption of moisture. Similarly, all the
noticeable plant changes on which weather predictions can rationally be based are owing to
variations in humidity, temperature, and sunshine. But however interesting, especially to
the student of plant physiology, plant signs
generally are but poor guides to a knowledge of
the coming weather.
WEATHER PROVERBS
81
BIRDS AND BEASTS
"She [the goose] is no witch, or astrologer, to divine
by the starres, but yet hath a shrewd guess of rainie
weather, bcing as good as an almanack to some that
believe in her."---Old Book, 1634. .
The scientific spirit of caution shown in this
quotation is most commendable. Indeed anyone who wishes a probably correct forecast of
the coming weather should pay no attention
whatever to the almanac, and almost as little
to the behavior of animals. Nevertheless, proverb literature contains page after page of
weather signs based on the behavior of living
creatures, from the bray of the jackass to the
bite of the flea.
Typical of the extravagant tributes to animals
as weather prophet? is this one to the pig, in
which he is credited with actually seeing the
wind-a one-time common belief:
"Grumphie smells the weather,
An' Grumphie sees the wun';
He kens when clouds will gather,
An' smoor the blinkin' sun."
Of course the degree of humidity, the temperature, the brightness of the sunshine, the
strength of the wind, and all other weather
states, d,O more or less affect the behavior of
82
WEATHER PROVERBS
many animals. Horses do sweat on hot, humid
days-so do human beings; when the au .
very damp the hound dog is lazier, if possible,
than usual; toads and snails do copte out more
when the sky is clouded and the air very damp
than on dry sunshiny days; and so on through
an endless list-actions, all of them, of th~
greatest interest to the physiologist, but com
monly of little worth as weather signs.
HES AND PAINS
"As old sinners have all points
0' th' compass in their bones and joints."
-BUTJ.D.
It is well recognized, and attested by a family
of proverbs, that those who are annoyed by
rheumatic pains, as also the dyspeptic and
. the neurasthenic, often are more than usually
troubled by their ills at the near approach of
rainy and generally bad weather. It was for this
reason that the wise, though, we may suspect,
not oVerjoyful, editor dedicated his almanac
to "Torpid Liver and Inflammatory Rm:umatism, the most insistent weather prophets known
to suffering niortall." For the eame :reason,
"
WEATHER PROVERBS
83
too, ~some unhappy proverb maker complained
that
"A coming "torm your shooting corns presage,
And aches will throb, your hollow tooth will rage."
However, such disagreeable signs are not
universally available, for, fortunately, there are
those who, like Tam O'Shanter, "never mind the
storm a whistle." Therefore, while the influences of the weather and its changes on our
feelings are worthy of careful study by both
the physiologist and the psychologist, such
phenomena are of only secondary value as a
popular means of weather prognostication. Besides, it is a method not assiduously cultivated.
In fact, those who are provided with this particular means to a weather prescience would
gladly be rid of it, while those who know it not
believe, as well they may, in the old adage that
says: "Where ignorance is bliss, 'tIs folly to be
wise."
PART II
Meteorological Paradoxes
INTRODUCTION
The scientific paradox is only an exception to
some familiar bu~ too inclusive generalization.
It, therefore~ has both the appeal of the riddle
and the charm of surprise-the surprise, the
instant the truth is seen, of a sudden and unexpected discovery-and thus affords the same
sort of intellectual delight that a certain student
of geometry once experienced. The proposition, one of Euclid's best, was the Pythagorean,
often carelessly called the pons asinorum. The
boy in question was of that sturdy type that
always insists on being "shown," and not understanding this propo~tion, flatly refused to accept it. A little coaching at the blackboard,
however, soon got him past his initial difficulties,
and so fixed his attention that as the truth
flashed upon him with the final "therefore,"
he blurted out, in the ecstatic surprise of an
Archimedes, and with the same oblivion to his
surroundings, "Well, I'll be damned if it ain't
so."
Wheth~r the following paradoxes do or do not
evoke such joyous acclamations as the one
just quoted, they, nevertheless, deserve to be
concisely stated and fully explained for they
express important facts of nature, unknown
to, or, at most, but vaguely realized by, the
average person.
87
88
METEOROLOGICAL PARADOXES
AIR PUSHED NORTH BLOWS· EASa'
This paradoxical behavior of the air is restricted, it should be said, to the northern
hemisphere; but it seems just as contrarious
on the other side of the equator, for there,
pushed north it blows west, pushed south it
blows east.
The push that causes the winds to blow is due
to the existence of unequal amounts of air
above a given level over adjacent regionsmore at the plac~ from which the air is pushed
than at the place towards which it is pushedand this in turn, usually, is due to the temperature differences, level for level, between the
atmosphere at the two places. Obviously there
tends to be, and, initially, actually is, a horizontal flow of the air (that is, a wind) at each
level, in the direction of the most rapid horizontal decrease of pressure at that level. Such
winds, however, frequently last so long (hours
at least) that their directions are profoundly
altered by a certain obscure factor, namely, the
rotation of the earth-the secret of fhe above
paradox-which is overlooked by almost everyone, and overlooked simply because its effect
on the shooting of a marble, the pitching of a
ball, and all the thousand other similar phenomena with which we are intimately familiar,
METEOROLOGICAL PARADOXES
89
is always negligible. Nevertheless, this effect
is ever present and much like, however feeble,
that which one experiences on walking, or trying
to walk, from. the center to the edge of a revolving turntable.
It is easy to demonstrate, as may be found in
many books and articles, that an object moving
in any horizontal direction tends so strongly
to turn to the right north of the equator, and
to the left south of it, as to exert a force, d,
against a restraint preventing such deflection,
given by the equation
d = 2mwv sin l
in which m is the mass of the object, v its speed,
l its latitude, and w the angular velocity of the
earth's rotation.
Consider, then, the effect of applying a
horizontal push of constant magnitude and
constant geographic direction to a mass of air,
m, and assume this air to be free from friction,
as it very nearly is when 1500 to 2000 feet
above the surface. Let m, figure 1, be this
mass of air, initially at rest with reference to the
surface of the earth; let it be in the northern
hemisphere, and let p be the push of constant
magnitude and constant direction, north. As
the mass moves it is simultaneously deflected
by the force d, explained above, from the north
90
METEOROLOGICAL PARADOXES
towards the east, and, owing to the 'curvature
of its path, a small centrifugal force is introduced. A little later, p may be resolved, as
shown, into two components, oneenormal and
the other tangential to the path of travel.
The first, like the deflective force d and the
d
p
m
p
FIG. 1. How AIR
PUSHED
ONE WAY
BLOWS ANOTImR
centrifugal force, has no effect on tItt speed,
being at right angles to the direction of 1l1otion,
while the second continuously increases the
speed, which, in turn, increases the deflective
force, and the deviation towards the east.
In the end, therefore, the component of P along
METEOROLOGICAL PARADOXES
91
the path is reduced to zero, and the direction
of travel becomes exactly east with the push
. p and the deflective force d equal to each other.
Hence winds. that are continuous for even a
few hours always blow more or less closely along
isobars, or paths of equal pressure, at a constant
height above sea level; hence at right angles
to, and not in the direction of, the sustaining
force-around centers of pressure minima and
maxima and not directly towards or from them.
No matter, therefore, how paradoxical it
may be, air pushed north does blow east (in
the northern hemisphere), pushed east it blows
south, pushed south blows west, pushed west
blows north; while in the southern hemisphere
it blows exactly contrariwise.
RAIN DRIES THE AIR
As everyone knows, there is !=ontinuous and
often rapid evaporation from practically all parts
of the eart.h's surface-oceans, seas, lakes, rivers,
damp soil, and growing vegetation. Nevertheless, the atmosphere as a whole never becomes
even approximately saturated. Water, indeed,
is always evaporating into the air and thus
constantly tending to saturate it; but, on the
92
METEOROLOGICAL PARADOXES
other hand, the air also is forever being gried
by the precipitation out of it of rain, snow,
and other forms of condensation. Whatever
the temperature and relative hu,midity of a
given mass of air on reaching any given place
along its convectional route, the total of water
vapor it may then contain obviously is less, in
general, than when it last left the surface of the
earth by the amount of precipitation in the
meantime abandoned by it. That is, on the
average, air descends to the earth drier than
it was when it ascended, and drier solely because of, and in proportion to, the amount of
precipitation that fell out of it during its convectional journey. In short, as the paradox
puts it, rain does dry the air-does prevent it
from becoming and remaining everywhere reekingly and intolerably humid, as it otherwise
would be.
MORE AIR GOES UP THAN EVER
COMES DOWN
This is, perhaps, about as incredible a paradox as can be found, for it seems flatly to
contravene the well known dictum that whatever goes up must come down. And, indeed,
to make the explanation of it entirely clear
METEOROLOGICAL PARADOXES
93
and, definite, it will be necessary to c()nsider
it independently under each of two distinct
conditions: (a) that the air is measured in terms
of volume, apd (b) that it is measured in terms
qf mass.
Measured in terms of volume. As everyone
knows, the vertical circulation of the atmosphere is only a gravitational phenomenon consisting of the sinking of relatively den~e, because relatively cold, air, and the conSequent
lifting or forcing up by it of adjacent air that
happens to be comparatively warm and light.
In short, contracted air descends and expanded
air ascends (is buoyed up by the descending
denser (iir). Hence, mass for mass, the volume
of the ascending air is always larger than that
of the descending air. The ratio between the
actual ascending and descending volumes, however, or masses, may be anything, as illu~trated
by chimney circulation in which the ascent is
restricted to a comparatively small volunle and
mass moving rapidly, while the descent extends
to a relatively large volume and mass settling
slowly. On the average, though, considering
both velocity of vertical movement and volume
occupied, or velocity times volume, the atmosphere as a whole is always ascending, a fact not
only interesting itself, but also of some importance to both the balloonist and the aviator.
94
METEOROLOGICAL PARADOXES
Measured in terms of mass. Whatever the
volume relations between ascending and ~ descending air may be, it would seem that at least
the mass that goes up and the ma~s that eventually ,. returns must certainly be the same.
But, on the contrary, they indeed are far from
it, for one of the important constituents of the
atmosphere, water vapor, often amounting in
places to 1 per cent, and occasionally to more
than 2 per cent of the whole, invariably ascends
as a gas, as a distinct part and parcel of the
air; but descends, in great measure, not as a
gas at all, not as any part whatever of toe air,
but as a liquid in the form of rain, or a solid, such
as snow, and hail.
Paradoxical, therefore, as it may be, a greater
mass of air actually goes up-more by at least
sixteen million tons per second, the measure
of world-wide precipitation-than ever comes
doWIl.
TO COOL AIR, HEAT IT
The air referred to in this seemingly absurd
statement is not that topsy-turvy kind Alice
might have found in Wonderland, but just that
ordinary kind in which we have always lived;
and the phenomenon itgelf, however contrary
95
METEOROLOGICAL PARADOXES
to experience it may seem, one of great importance and almost continuous occurrence.
"
METERS
1300
'A
1200
'-.A
1100
'
E.
"1'\
i'
1000
900
"1'~"
,
800
W
"", ,<',", ,
'"
700
,,~
600
I--
,
,'\.~
500
j
'~
" w'
"-1\,
-C'"
400
1',
300
~,
200
:,"
E"
100
,S-,
,8
~
0
a
2
1
~
FIG. 2.
3
4
5
6
7
8
9
10
II
VERTICAL TEMPERATURE GRADIENTS OF FREE
12
I
DEGREES CENTIGRADE
AIR
This paradoxical result is easy to explain ''lith
a diagram. To this end let AB and A'B',
figure 2, be two adiabatic gradients of the
96
METEOROLOGICAL PARADOXES
free air; that is, let each indicate a temperC),ture
change of 1°C. for every 100 meters change in
elevation (1°F. for every 182 feet)-approximately the relation between the. temperature
and elevation of a rising or falling mass of air
that during its travel neither gains heat from,
nor loses it to, any outside object, such as the
surrounding atmosphere. Let EE be any actual
temperature gradient (nearly always less than
the adiabatic), in this case 1°C. per 120 meters
change of elevation. If, then, under these
conditions, a mass of air having the temperature
and elevation indicated by G' , say, of the figure,
be heated 1°C., or shifted in the figure to W', it
will correspondingly expand and consequently
be forced up by the surrounding denser airwill ascend, as we say. As it rises, it will cool,
by expansion, along the adiabatic gradient A'B',
and, therefore, will come into equilibrium with
the surrounding atmosphere where this gradient
intersects the actual gradient EE, or at the
level and temperature indicated by W. Clearly,
then, under the assumed conditions, such as
are very common in nature, a mass of air heated
1°C. (1.8°F.) rises 600 meters (1968 feet), and
in so doing cools 6°C., or to a temperature soc.
lower than it had before it was heated. Of
course, the warm air does not rise strictly
adiabatically, though probably very nearly so;
METEOROLOGICAL PARADOXES
97
but in so. far as it actually does lose heat it
comes to equilibrium at a correspondingly lower
level and warmer temperature.
I t is precisely this paradoxical process of
cooling by heating, the heating being mainly
at the surface, however, that leads to the formation of cumulus clouds and generates the
familiar "heat" thunderstorm. In fact, it is
quite possible to produce a cumulus cloud, and
even a local shower, through the action of a
large surface fire. In the case of a forest fire it
should be noted that though the combustion
adds, by the chemical actions involved, much
water vapor to the air, in weight five-ninths,
roughly, that of the fuel, even when it is the
driest of wood, nevertheless, the cumulus cloud
over the fire is due, essentially, to the expansional
or dynamical cooling of the ascending air.
TO WARM AIR, COOL IT
This pa.radox is the converse of the one just
discussed, and is readily explained in much the
same way. Referring again to figure 2, let a
mass of free air having the altitude and temperature indicated by W in the figure, be cooled
1°C., or its position shifted to C. It will at
98
METEOROLOGICAL PARADOXES
once become denser than it was, follow~ the
adiabatic gradient, AB, as it falls to lower
levels, and, therefore,' come to rest at the level .
and temperature indicated by a, or at the
intersection of the adiabatic gradient followed
and the existing gradient. That is, as a result
of the initial cooling of 1°C., the given mass of
air will fall 600 meters and become SoC. warmer
than it was before it was first cooled. In so
far, however, as the falling air gains heat from
the surrounding .warmer atmosphere, it will
come to rest at a correspondingly greater elevation and lower temperature.
This paradoxical phenomenon of warming
by cooling is very frequently and very prettily
illustrated by the evening disappearance of
small detached clouds, such as alto-cumuli,
fracto-stratus, etc. As soon as the sun has
set, these clouds and, through them, the air
in which they are enmeshed, cool more rapidly
than does the surrounding clear atmosphere.
They, therefore, are dragged to lower levels
by the falling air where they warm up to higher
temperatures than they originally had, and
evaporate.
It will be interesting, in this connection, to
note the logical effect of a certain ingenious,.
often proposed, and at least once experimentally
tried, m~thod of artificially inducing rainfall,
METEOROLOGICAL PARADOXES
99
nam~ly, the liberal sprinkling of a cloud mass
with liquid air. The result is, of course, an
initial cooling of the cloud, followed, as above
explained, by its fall to a lower level and its
consequent much greater warming. Instead of
rain being induced by this process, as its many
inventors would confidently expect, the chilled
cloud is certain to grow warmer and diminish
in size, and, if considerably chilled may grow so
much warmer as to disappear entirely. Indeed,
this particular liquid air scheme is not a rainmakiIt'"g process at all, but, on the contrary, a
rain deterrent!
NOT AIR THAT IS HEATED, BUT AIR
THAT IS NOT HEATED, IS
THEREBY WARMED
This particular paradox may ~uggest the
superiority of "absent treatment;" nevertheless, it is perfectly sound. Heated air, as we
know, is ,.driven up by the surrounding denser
air, and cooled by its resulting expansion, but
the air that drives it does so by itself dropping
to a lower level, where it is more or less compressed and correspondingly warmed. In other
words, while the particular air that was heated
100
METEOROLOGICAL PARADOXES
rises and gets colder than it was initially, other
air that was not heated at all falls lower and
thus gets warmer. It is not the air that is
heated, but air that is not heated, that gets
warmer.
NOT AIR THAT IS CHILLED, BUT AIR
THAT IS NOT CHILLED, IS
THEREBY COOLED
The explanation of this paradox is very similar
to that of the one just given, and is equally
simple. As the chilled air descends, certain
other air is thereby raised and, by its consequent expansion, cooled. That is, while the
particular air that was cooled descends and thus
gets warmer than it was originally, other air
that was not chilled at all is forced up, expands,
and gets colder. It is not the air that is chilled
(unless it happens to be on or near the surface
of the earth, where it cannot fall to a low:er
level) but air that is not chilled, 'that. gets
colder.
METEOROLOGICAL PARADOXES
101
MQCING BRINGS THE AIR TO A NONUNIFORM TEMPERATURE
To the laboratorian, familiar with beakers and
calorimeters'; to the housewife, skilled in the
art of the cups and the kettles; and to all the
rest of us, nothing is more certain-nothing
more in accord with daily experience-than that
vigorous stirring establishes a uniform temperature throughout the agitated medium. And
indeed this conclusion is quite correct in respect to the particular things we are likely to
have in mind, but it does not apply to the
open atmosphere. In fact if the temperature
of the atmosphere were uniform through any
considerable altitude, a complete stirring of it
would immediately destroy this uniformity.
Let, then, the atmosphere, whatever its initial
temperature distribution, be thoroughly mixed
without the addition or subtraction of heat.
This will bring it into such state (that of neutral
equilibrium) that any portion of it on being
moved to a different place without the addition
or subtmction of heat on the way will, on arriving at that place, have the same temperature
as the then adjacent air at the same level.
That is, it will have the same potential temperature throughout, or same actual temperature
when subjected to the same pressure. The
102
METEOROLOGICAL PARADOXES
truth of the above statement is obvious from the
fact that any temperature difference that ~ight
be developed by a transfer of the kind mentioned clearly could be reduced. by further
mixing.
But as a mass of this air is carried to higher
levels it continually expands against the diminishing pressure-diminished by the weight of
the air passed through-thereby does work at
the expense of its own heat energy and Correspondingly cools to lower temperatures. The
ratio of this cooling to increase of altitude
evidently depends upon the nature of the gas
and the change of pressure. In the case of our
own atmosphere it is approximately 1°C. per
100 meters.
Although, therefore, stirring does bring an
incompressible liquid to a uniform actual temperature, it brings the atmosphere only to a
uniform potential temperature, or an actual
temperature that is very non-uniform, that, in'
fact, gets colder and colder at the rate of 1°C.
for each 100 meters increase of elevation.
METE.OROLOGICAL PARAbOXES
103
THE NEARER THE SUN, THE
COLDER THE AIR
The familiar fact that with increase of elevation and consequent approach (during the daytime) to the sun, the air nevertheless gets rapidly
colder, at least through the first 10 kilometers
(6.2 miles), is very puzzling to the average
person if he tries to explain it. Nor, indeed, is
the explanation of this phenomenon quite so
simple and obvious as we sometimes are asked
to believe. Essentially, however, this temperature distribution depends on the following facts:
1. The atmosphere, as we know from observation, lets heat and light pass through it so
readily that half, roughly, of the effective
radiation received from the sun, that is, half of
the portion absorbed' by the earth and the
atmosphere jointly and not lost by reflection,
goes directly to warming the surface of the
earth. Consequently, it is this surface, where
the energy absorption is concentrated, and not the
atmosphere, through which absorption is diffused, th:;lt is most strongly heated by insolation. The heated surface in turn warms the
air above it, partly by contact, and partly by
the long wave-length radiation it emits, and of
which the atmosphere is far more absorptive
than it is of, the comparatively short wavelength solar radiation.
104
METEOROLOGICAL PARADOXES
2. Furthermore, and this is an eq'Hally.,vital
part of the explanation, the lower atmosphere
(below about 10 kilometers, 6.2 miles), under
all ordinary conditions emits more radiant
energy than it absorbs-the difference necessary
to maintain the nearly constant temperature
that obtains at each level being supplied by
convection. It is these two phenomena, (a)
the surface heating (warming below), and (b)
the net loss of heat by radiation (cooling above),
that together establish and maintain the vertical
convections of the atmosphere under which,
since the descending portions grow warmer
through compression, and the ascending colder
through expans'lOn, the whole of the convective
region is made to decrease in temperature with
increase of elevation.
But since the coefficient of absorption of the
air, as of other objects, changes but little, if
at all,· with the temperature, while its emissive
power decreases rapidly as it grows colder, and
since the intensity of the incident terrestrial (including atmospheric) radiation remains roughly
constant up to an altitude of man)' kilometers, beyond the first 4 or 5, it follows that
the upper limit of the convective region is not,
as formerly supposed, the outermost extent of
the atmosphere, but at that elevation (10 to 12
kilometers, 6.2 to 7.5 miles, above sea-level)
METEOROLOGICAL PARADOXES
105
at which the temperature is so low (-55°C.,
or -67°F., roughly) that the loss of heat by
radiation is no longer in excess of, but now equal
to, its gain, by absorption. Beyond this level
temperature does not decrease, or does so but
slightly, with increase of elevation; nor would
it so decrease (at least not at anything like the
present rate) beyond any level above the thin
conducting surface layer, at which absorption
and radiation became equal.
In short, then, the air grows colder with
elevation-the nearer the sun the colder the
air-because (1) owing to its transparency to
solar radiation it is heated mainly at the surface of the earth, and (2) because, at ordinary
temperatures, it emits more radiation than it
absorbs. These together so affect the density
of the atmosphere as to induce vertical convections, and thereby to establish and maintain,
throughout the region in which they are active,
a rapid decrease of temperature with increase
of elevation.
THE COLDEST AIR COVERS THE
WARMEST EARTH
This paradoxical statement refers to the air
of the isothermal or constant temperature re-
106
METEOROLOGICAL PARADOXES
gion above the limit of vertical COI1Vection,
with respett to which air it is a well known
truth whatever the explanation may be·
It has, doubtless, been known since the dawn
of intelligence that the top of a mOlmtain is
cooler than the adjacent valleys, and that the
highest among neighboring mountains has the
coldest top. And for much more thaj:1 a century, actually since November 30, 178·4, it has
been known, from observations by balloonists,
that the temperature of the free air also decreases with height, at least up to such altitudes
as were attained by manned balloons. About
the dase. at the. la.st c.e.n.t1.lt'j, hawe.ve.r., it became evident, through records obtairted with
sounding balloons, that in middle latitudes the
temperature of the atmosphere continuously
decreases, on the average, with increase of altitude up to only 10 or 12 kilometers above sea
level, and then becomes substantially constant.
Numerous subsequent records obtained at many
places have shown the additional surprising
fact that this isothermal region, or str~tosphere
as it generally is called, begins at a higher level,
and is colder, over equatorial regions than over'
any other part of the world. Indeed, it seems
to be lO°C. to 15°C. colder over the equator,
where its average temperature is roughly -70°C.
(-94°F.), than, for instance, over the polar
circles.
METEOROLOGICAL PARADOXES
107
The temperature of the stratosphere appears
to be determined chiefly by the intensity of
the outgoing radiation from the earth and the
intervening water vapor, hence it seems to follow
that this radiation must be less intense over
regions near the equator than over those of the
middle and higher latitudes; a conclusion that
merely shifts the burden of explanation from
one' paradox to another.
Obviously, the earth as a whole must emit,
on the average, the same amount of radiant
energy day by day that it absorbs, but the
distributions of the absorption and emission
certainly are different. In equatorial regions
upward movement of the atmosphere is so
general and so strong that high haze, cirrus,
and other types of clouds are exceedingly common, and the atmosphere necessarily humid
and, therefore, strongly absorptive of earth
radiation to great altitudes, especially as anticyclones, or extensive areas of descending air,
are there unknown. Clearly, then, a large
part of the radiation through the stratosphere
of this region must come from the clouds and
water vapor that are very high and correspondingly cold, and therefore its intensity, it would
seem, must. be correspondingly feeble. The
pent-up heat below presumably finds an outlet
through horizontal circulation and the conse-
108
METEOROLOGICAL PARADOXES
quent increase of radiation from lower .Jl.ild
warmer levels in extratropical latitudes.
This, perhaps, is at least the partial explanation of why the minimum temperature of the
stratosphere occurs over the tropical regionswhy the coldest air covers the warmest earth.
AS THE DAYS GROW LONGER, THE
COLD GROWS STRONGER
This old proverb paradox expresses the w,ell
known fact that our lowest temperatures do
not occur at the time of the shortest days,. or
when the heat supply from the sun is least,
but some time afterwards, when the days have
grown longer and the supply of solar heat has
increased. That is, over a considerable period,
the air grows colder as the sun grows warmer.
In the far interior of continents, especially if
arid, this lag may not be more than a couple
of weeks, but on many islands and along several
coasts whose winds are prevailingly onshore, it.
is from one to two months.
To understand this phenomenon consider an
object (representing the earth) suspended within a thermally opaque shell (assumed the source
of incoming radiation) whose temperature is
METEOROLOGICAL PARADOXES
109
everywhere the same. For simplicity let the
enclosed object be a "black body," that is, a
full radiator and perfect absorber. Let the
absolute temperature of the shell be T and that
of the enclosed object T ± t. Under these
conditions the rate of heat absorption by the
suspended body is AKP ( a full radiator gives
off energy in proportion to the fourth power of
its absolute temperature, while a perfect absorber takes up every ray that falls upon it),
where A is its "equivalent" area and K the
"black body" coefficient, while the rate of its
emission is AK(T ± t)4. If, now, t is small in
comparison with T, the rate of net gain or loss
of heat by the· enclosed object is 4AKT3t, approximately, and the ratio of its rate of temperature increase or decrease to the temperature
difference, t, a constant, inversely proportional
to its heat capacity, assuming high conductivity.
The limiting temperature' T would, therefore,
never be fully attained, but forever approached
closer and closer. Clearly, then, if the temperature of the shell were T and that of the
enclosed object T + t, the latter would continue
to grow colder through any finite time unless,
and until some time after, the temperature of
the shell were raised above the then temperature
of the enclosed object.
110
METEOROLOGICAL PARADOXES
The reasoning in this special case appIies.~also
to the normal daily temperature of the atmosphere (substantially that of the surface of the
earth), provided, as will be assumed for the
moment, that there is neither circulation nor
any thermal effects due to water transformations-freezing, thawing, etc. It applies because the normal daily loss of heat through
radiation to space by any given region is as
though it were a full radiator at a certain temperature, and its normal daily gain of heat from
the outside as though the region in question were
completely canopied by another full radiator
also at a certain (generally different) temperature.
During the autumn, therefore, while there is
still stored in the earth much of its summer
gain of heat, and while the daily supply of
energy from the sun is growing less and less
per unit area, the average 24-hour temperature
of the surface, and of the surface air, must be
appreciably higher than that of equilibrium
with the simultaneous incoming radiationhigher because of the additional supply of heat
by conduction from its reservoir beneatl). the
surface. Now, as the summer storage of ~eat
iIi the earth is very large and also near the
surface (but little penetrating beyond a depth
of 5 or 6 meters, 16 to 20 feet) itis obvious from
METEOROLOGICAL PARADOXES
111
the ::.preliminary explanation above that the
minimum temperature cannot occur until some
time after the winter solstice, the date of minimum supply, of heat by the sun; not, that is,
until the days have again grown longer and the
rate of supply of solar heat materially increased.
Furthermore, this delay clearly must depend
on latitude, nature of surface, and a number of
other factors.
The date of this minimum temperature is
still further delayed, in many places, by the
trend of warm ocean currents and the warmer
surface drifts toward higher latitudes, and by
onshore winds. It is also affected, though
probably but slightly, by the thermal effects of
freezing, thawing, evaporation, and condensation.
The storage of heat in the earth while the
days are long, its gradual delivery back to the
surface while the daily supply from -the sun is
comparatively small, and the poleward drift of
warm water at all seasons, together produce, as
explained, the paradoxical result so admirably
expressed' by the proverb,
"As the days grow longer,
The cold grows stronger."
112
METEOROLOGICAL PARADOXES
AS THE NIGHTS GROW LONGER, TME
HEAT GROWS STRONGER
It will be recognized at once that;, this paradox
is only the counterpart of the one just discussed,
and that it must also have substantially the
same explanation.
As the days continue to grow longer after the
time of minimum temperature, it is clear that
from then on for several months the earth's
gain of heat must be at a faster rate than its
loss-that, in terms of the above explanatory
hypothesis, the effective temperature of the
shell is T and that of the enclosed object T - t.
Under these conditions the thin layer of the
earth affected, because of its large but finite
heat capacity, must continue to grow slowly
warmer until the incoming radiation has become
less, that is, until the nights. have grown perceptibly longer.
This .lag, the lag of maximum temperature
after the summer solstice, is also, like the lag
of minimum temperature after th~ winter solstice, a function of location; generally least in
the interior of continents and greatest on .islands
and near coasts whose prevailing winds are
onshore.
METEOROLOGICAL PARADOXES
113
AS THE'SUN DESCENDS, THE' TEMPERATURE ASCENDS
By this paradoxical expression it is only
meant to state tersely the well known fact that
the warmest time of the day is not when the
sun is on the meridian, or when insolation is
greatest, but sometime in the afternoon when
the sun has descended considerably from its
maximum elevation. As everyone knows, night
cooling reaches its greatest effect, on the average, just after daybreak. Hence, and for the
reasons explained above, as the sun ascends the
temperatures of the warming surface of the
earth and of the lower air lag behind equilibrium
with the incoming radiation, and continue to
do so until the intensity of the insolation has
passed well beyond its maximum. That is,
the temperature continues to rise for some time,
generally two to four hours, after the sun has
crossed the meridian, just as, and for the same
reason that, the average daily temperature
increases for weeks after the summer solsticeas the sun begins to descend from its highest
point the temperature continues to ascend.
114
METEOROLOGICAL PARADOXES
WHEN A THAW COMES ON, THE FOOST
GOES DOWN
The truth of this paradox is sometimes
exasperatingly proven by the bursting of buried
pipes after the surface of the ground had begun
to thaw and we had comforted ourselves with
the belief that all danger of a water famine
was over.
Suppose there has been a protracted spell of
very cold weather, bringing the ground to 20°F.
belmv zero at the surface, zero F. at the depth
of 1 foot, and to the freezing point, or 32°F.
at the depth of 3 feet. Now, let the weather so
moderate that the temperature of the air shall
be above freezing. Pretty soon the surface of
the ground will also warm up, more or less,
by heat absorbed from the air, ancC in turn,
transmit heat by conduction to the colder earth
next below. At the same time heat will con~
tinue to be conducted from the deeper layers
upward wherever the decrease of temperature is
in that direction, as, for instance, at the under
surface of the frozen earth. Furthermore, at
this under surface the rate of temperature
decrease upwards is, at first and for some time,
greater than the rate of temperature increase
downwards. Hence, under these conditions, the
soil at this boundary loses heat upward faster
, METEOROLOGICAL PARADOXES
115
tha.Il it gains heat from below and the level of
freezing continues to go deeper for a while, even
several days-weeks in extreme cases-after the
surface had ,begun to thaw.
Of course the going down of the frost (freeze)
does not wait on the coming of a surface thaw,
but neither does it stop going down at once as
soon as the surface is warmed. After the warm
weather has begun, the thaw extends deeper
and deeper, and so too, for a time, does the
freeze. In truth, then, and at times a truth of
much practical importance, when a thaw comes
on, the frost goes down.
Similarly, under circumstances easily imagined and that now and then occur, when a frost
comes on, the thaw goes down.
THE
ABSOLUTE MAXIMUM DIURNAL
INSOLATION (HEAT SUPPLY) IS
AT THE SOUTH POLE
If I i~ the solar constant, or quantity of solar
energy per minute per unit area, normal to the
incoming radiation at the limit of the atmosphere, then the total amount Q of solar energy
per any consecutive twenty-four houn, per
unit area of a horizontal surface, also at the
116
METEOROLOGICAL PARADOXES
limit of the atmosphere, is given by the eQuation
1440 (
.
.
.
Q = _ - I H sm 1 sm d + cos 1 cos d sm II)
~
~
in which 1 is the latitude of the place in question,
d the declination of the sun at the time, H the
hour angle, in radians, between noon and sunrise, or sunset, and ~ the ratio of the Clrcumference to the diameter of a circle, 3.1416,
nearly.
A great deal of interesting information is
contained in this equation. The most interesting, perhaps, is the fact that if the value of
Q for the equator at the time of the vernal
equinox be represented by 1000, then that of
the north pole at summer solstice is 1202, and
that of the south pole at the corresponding
solstice 1284; each being greater than the value
of Q at that time for any other place in either
hemisphere. The advantage in favor of the
south pole is owing to the fact that the earth
is then near perihelion, and, therefore, closer
~o the sun.
Not only does the absolute maximum diurnal
insolation at the limit of the atmosphere occur
at the south pole, but, owing to the great elevation of the south polar region, the dryness of
its atmosphere and its comparative freedom
METEOROLOGICAL PARADOXES
117
from dust, so also does the corresponding maximum at the surface of the earth.
The days, however, of continuous and intense sunshme at the poles are comparatively
few, nor is this insolation very effective in
raising the temperature, owing to the high
reflecting power and great heat of fusion of the
always-prevalent snow and ice. And so it
happens that although for a time every year
each pole receives more solar heat during any
consecutive twenty-four hours than does any
other place on the earth, it is always cold; and
the south pole, though having the greater
maximum diurnal insolation, is the colder of
the two, owing to its elevation and greater
distance from open water.
THE HOTTER THE SUN, THE COLDER
THE EARTH
It is not yet universally conceded that this
paradox, "the hotter the sun the colder the
earth," really is true; but the evidence in favor
of it is already very strong. It is known, for
instance, that several extensive studies of the
temperature records of the earth have all shown
that, on the average, it is a little colder during
118
METEOROLOGICAL PARADOXES
the years of sunspot maxima than during. the
years of sunspot minima. Furthermore, numerous careful measurements of the solar radiation
made during the past dozen years or more, seem
to compel the assumption, at least tentatively,
that the effective temperature of the sun is
greater during spot maxima than during spot
mmlma. If, then, both these conclusions are
true-if the temperature of the earth is lowest
during spot maxima and the solar constant
highest-it follows that the above paradox is
also true.
But by what possible process can the earth
get colder when the sun grows warmer? It
has been suggested that the increase of the solar
constant causes a corresponding increase in the
atmospheric circulation, and, therefore, a decrease in the surface temperature, owing to the
greater flow of cold air from the higher towards the lower latitudes. But the very great
mixing of the convective portion of the atmosphere, and the consequent prevention of the
(ormation of over- and underflowing strata, seems
to render this suggested explanation untenable.
The key to this paradox, may, perhaps, be
found in the greater extent and density of the
solar corona at the times of spot maxima than at
the times of spot minima. The corona, since in
large measure it is only so much dust about the
METEOROLOGICAL PARADOXES
119
sun., obviously must interfere with the passage
of radiation through it, and to a far greater
extent with the ultra-violet radiation than with
the visible -3.nd infra-red. Hence, during spot
maxima, or when the solar atmosphere is dustiest,
the solar energy must, it would seem, be poorest
in ultra-violet radiation.
Now, when cold dry oxygen, such as exists
in the upper atmosphere, is acted upon by
certain regions, at least, of the ultra-violet
spectrum, some of it is converted into ozone, a
substance known to be in the upper atmosphere
to a far greater extent than in the lower. Hence
when sunspots are most numerous the upper
air should contain a minimum amount of ozone.
But ozone is intensely absorptive of earth radiation and that too in the spectral region of its
greatest intensity, and where water is least
absorptive and carbon dioxide not at all. That
is, at the time of spot maxi.ma when the solar
constant is (apparently) greatest, the earth's
blanket of ozone is (presumably) least. Even,
therefore, if the earth should be receiving an
increasea amount of heat at this time it might,
nevertheless, grow slightly colder because of
the coincident depletion of the heat conserving
blanket of ozone.
A greater general prevalence of' cirrus and
cirrus haze during spot maxima than during
120
METEOROLOGICAL PARADOXES
spot minima (indicated by certain observatipns)
would also account for this paradox; because
such clouds, owing to the size of their particles,
shut out the short wave-length solar radiation
more effectively than they shut in the long wavelength earth radiation. And perhaps these
clouds really are generally most prevalent during spot maxima, and, therefore, at least a
contributing factor to the cause of the corresponding temperature minima. At any rate
the auroras are then most frequent, and they,
perhaps, generate nitrous oxide and some other
hygroscopic compounds which, because of their
density, slowly fall to the cirrus level where
they may produce cloud particles in an atmosphere whose humidity is much below that
which otherwise would be essential to cloud
formation.
The maximum, then, of the cirrus screen and
the minimum of the ozone blanket, coincident
with the highest temperature of the sun, may
very well account for the above paradox,-the
hotter the sun, the colder the earth.
METEOROLOGICAL PARADOXES
121
TIiE COOLER THE SUN, THE WARMER
THE EARTH
This paradox is practically included in the
one just discussed. It means that at the times
of sunspot minima, when the solar constant
seems to be least, the average temperature of
the earth is highest.
At the times of spot minima the solar atmosphere is clearest; the extreme ultraviolet radiation presumably, therefore, at a maximum;
the upper atmosphere richest in ozone, and the
earth most conservative of its heat, and, because of the minimum (if that be the case) of
cirrus, also most receptive of solar radiationso receptive and so conservative, perhaps, as to
gain slightly in temperature despite the decrease in the heat supply.
THE COLDER THE DAY, THE HOTTER
THE SUN
The h~at of the sun is measured by exposing
a suitable absorber, called a pyrheliometer
(sunfire measurer) squarely to the incoming
radiation. The less the depletion of this radiation, whether by absorption or scattering, during its passage through the atmosphere, the
122
METEOROLOGICAL PARADOXES
more intense it is at the surface of the eat;,ththe hotter the sun, as we say.
Now, the chief absorber of solar radiation in
the atmosphere is water vapor, while dust is
effective in scattering it. But the colder the
air the less the water vapor present, and also,
as a rule, the less the dust for there are then
few if any rising currents to carry dust up.
In fact, at such times the atmosphere is apt to
be slowly descending, and for that reason, too,
comparatively dry and dust free. That is,
the colder the air the better, in general, it
transmits the solar radiation-the colder the
day, the hotter the sun.
THE CLOSER THE SUN, THE COLDER
THE SEASON
This striking paradox, which might equally
well be written, "the farther the sun, the warmer
the season," applies to the northern hemisphere
only, and is easy to understand.
The orbit of the earth, as every astronomer
can tell us, is an ellipse, with the sun in one
of the foci, and of such elongation that our
maximum 'ilistance from this source of heat and
light is about 3.3 per cent greater than the
METEOROLOGICAL PARADOXES
123
mmimum distance, which gives 6.6 per cent
difference between the corresponding intensities
of the received radiation.
Now, it 80 happens that at present, and it
will continue so for centuries, we are nearest the
sun in January, our coldest month, and farthest
from it in July, our warmest month. Of course
it is the shortness of the days and the low elevation of the sun that' makes January and the
other winter months cold (in the northern
hemisphere) in spite of our then nearer approach
to the sun, and the long days and high elevation
of the sun that, on the other hand, makes the
summer months warm in spite of our then
greater distance from the sun.
But whatever the details of the explanation,
it is literally true that, for the northern hemisphere, the closer the sun, the colder the season,
and the farther the sun, the warmer the season.
TIlE SUN RISES BEFORE IT IS UP
This paradox about the sun rising before it is
up is equally true of the moon and the stars,
and is also one of the best known and easiest
explained of all meteorological panidoxes.
124
METEOROLOGICAL PARADOXES
Everyone is familiar with the fact that as
light passes slantingly from one medium to
another, as from air to glass, for instance, it
does not continue on in the same straight line,
but abruptly changes direction at the interface
according to well-known laws. And the same
thing is true of the rays of light that pass from
space into and through the atmosphere of the
earth; except that, in this case, as the density
of the atmosphere gradually increases from
zero at its outer boundary to a maximum at
the surface of the earth, so too the change in
direction of the entering light is equally gradual.
The total change of direction by the time the
surface of the earth is reached depends upon the
wave-length or color of the light; the slope at
which it enters, or zenith distance of the luminous object; the temperature and barometric
pressure at the place of observation; the humidity; and several other minor factors. On the
average, however, light from a star, for instance,
that appears to be 90° from the zenith, and,
therefore, on the horizon-just rising say-has
been bent out of its original course by about
34.5'. That is, it comes into view (rises)
while actually more than half a degree below
the horizon. And as the angular diameters of
the sun ana the moon are each less than this
horizon refraction, it follows that when the sky
METEOROLOGICAL PAR_t\DOXES
125
sqfficiently clear the whole of either luminary
may be seen before even its topmost portion is
up; that is, before it is geometrically above the
horizon, or ,actually within 90° or less of the
zenith.
1S
THE SUN SETS AFTER IT IS DOWN
Since the virtual wave length of a given
radiation of celestial origin, and, therefore,
the value of its astronomical refraction is modified by the rotation of the earth, as are also
certain scintillation phenomena, it follows that
the above paradox is not identical with the one
just explained. Nevertheless, as the spectra
of the ~tars and other celestial objects all overreach the visible portion at each end, it follows
that this modificati.on, this Doppler effect,
produces no appreciable alteration in the ensemble of the light from anyone-merely a
minute shift of its entire spectrum that can be
detected only in the positions of definite lines.
But even this displacement of the spectral
lines, due to the rotation of the earth, is far too
small, roughly one three-hundreth the distance
between the sodium D's, to affect, detectably,
astronomical refraction. Hence as the sun,
the moon, and the stars all rise beflire they are
up, so too they must all set only after they have
gone down.
Sans Tache
Sans Tache
N THE" elder days of art" each artist or craftsman
enjoyed the privilege of independent creation.
He carried through a process of manufacture from
beginning to end. The scribe of the days before the
printing press was s~ch a craftsman. So was the
printer in the days before the m~chine process. He
stood or fell, as a craftsman, by the merit or demerit
of his finished product.
I
Modern machine production has added much to the
worker's productivity and to his material welfare; but
it has deprived him of the old creative distinctiveness. His work is merged in the work of the team,
and lost sight of as something representing him and
his personality.
Many hands and minds contribute to the manufacture
of a book, in this day of specialization. There are
seven distinct major processes in the making of a book:
The type must first be set; by the monotype method,
there are two processes, the "keyboarding" of the MS
and the casting of the type from the perforated paper
rolls thus produced.· Formulas and other intricate
work must be hand-set; then the whole brought together (" composed") in its true order, made into pages
and forms. .J'he results must be checked by proof
reading at each stage. Then comes the "make-ready"
and press-run and finally the binding into volumes.
~l of these processes, except that of binding into cloth
or leather covers, are carried on under our roof.
The ·motto of the Williams & Wilkins Company is
Sans Tache. Our ideal is to publish books "without
blemish"-worthy books, worthily printed, with worthy
typography-Dooks to which we shall be proud to
attach our imprint, made by craftsmen who are willing
to accept open responsibility for their work, and who
are entitled to credit for creditable performance.
The printing craftsman of today is quite as much a
craftsman as his predecessor. There is quite as much
discrimination between poor work and good. We
are of the opinion that the individuality of the worker
should not be wholly lost. The members of our staff
who have contributed their skill of hand and -brain to
this volume are:
Keyboard Composition: Tabular work by
straight matter by ELEANOR LUECKE.
Casting:
AGNES
HARTMAN;
CHARLES AHER, KENNETH BROWN, HAROLD REUSCH-
LHW, MARLON ROBINSON, GEORGE SMITH, ERNEST W ANN.
Hand
Composition:
ZEDDIE
BREITHAUPT,
WILLIAM
FITE,
HARRY HARMYER, RAY KAUFFMAN, RICHARD KING, HERBERT
LEITCH,
VERNON
LYONS,
Moss,
GEORGE
HENRY
MuRPHY,
\VILLIAlI -i~OSEK, EDWARD RICE, WILLIAlII SANDERS.
Press
Work:
RAYlIIOND
CLEMMlTT, HE~"'RY
GEORGE LYONS.
Proof Readin.g:
Binding:
BAUER,
ECKERT,
Overlay by
ANDREW
BECKER,
FRANK JONES,
JAMES
PAUL
KOLBE,
WILLIAM HARRISON, JR.
RUTH JONES,. ETHEL STRASING~R.
:MADELINE COULTER, MARGARET LAVIN, IDA KISTLER,
ANNA HAZARD, BEATRICE BLATCHLEY •.
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