InNo. 131, the ice crystal has at last begun to assume definite form, and its hexagonal shape is more clearly defined; while inNo. 132, we have the completed flower-like outline, and in Nos.133and134the finished ice flower with its air inclusions of light and shade perfected. This shows the entire process of growth of the commonest type of these ice crystals, after which process they lose their identity and merge into the solid ice film.
However, ice film growth is not wholly supported in this manner, for branches often form upon the under side of the ice film, and grow downward into the water, as shown in photographNo. 135, which is a section of ice with fern-like crystal-growth growing down into the water, thus aiding in growth and solidification. Each type of crystal, and there are five, represents some different characteristic growth—the long, narrow, needle type, the simple stars of six points, and the spherical or discoidal forms; also those resembling coral-like formations.
120. Branchy trigonal crystal
120. Branchy trigonal crystal
121. An uncommon type
121. An uncommon type
PhotographNo. 136shows how individual ice flowers hamper each other in growth; that the points reaching out into clear water grow and draw to themselves with greater freedom the water molecules, while the points intruded upon or crowded out by other crystals or flowers, cease to grow, and do not interfere with the growth of others.
Nos.137and138are still other forms of ice-growth, the needle-like, lance-like form which we may frequently observe pushing out from the banks of a small pond or brook. These needle-like forms of ice eventually acquire branches about their entire radius, which grow and merge, with other ice flowers of different types, into solid ice upon the surface of the water.
No. 139shows this type of ice-crystal completed. These ice-crystals form and rise like magic in early winter, especially upon and around the new ice upon the edges of small brooks, and streams.
“Sometimes the roof no fretwork knewBut silvery mosses that downward grew;Sometimes it was carved in sharp reliefWith quaint arabesques of ice-fern leaf.”
“Sometimes the roof no fretwork knew
But silvery mosses that downward grew;
Sometimes it was carved in sharp relief
With quaint arabesques of ice-fern leaf.”
Another very interesting example of ice-growth and formation which we occasionally discover upon the window-panes, and which should not be confounded with the frost work etchings, as it is in reality a thin transparent ice film, which frequently assumes exquisite formations and patterns. InNo. 141athe coral-like branch is a beautiful example of this window-pane ice, while upon the same pane of glass in precisely the same temperature we find another type, as141bresembling somewhat the transparent wing of an insect. There are but two distinct types of the ice film etchings, and they are classified as the feather form and the arborescent types. It is presumed that the forming of types is largely governed by the varying thickness of the glass upon which the ice film is deposited, and to the presence or absence of minute frozen particles of ice beneath the film. The feather form seems to develop upon cooler positions of the glass, and where the water film is thinnest.
122. One of the most elaborate crystals shown. Notable for its very dark centre and the curious detail of its border
122. One of the most elaborate crystals shown. Notable for its very dark centre and the curious detail of its border
123. A rare design because of its open petal-like formation. Usually such crystals are solid
123. A rare design because of its open petal-like formation. Usually such crystals are solid
124. Very frigid altitude crystal having remarkably etched centre
124. Very frigid altitude crystal having remarkably etched centre
125. A snow crystal covered with granular deposit of frost
125. A snow crystal covered with granular deposit of frost
Nos.142,143, and144are all rare examples of window ice. No. 16 shows to perfection a greatly magnified section of the coral-like tracings in detail. This window-pane ice, unlike the frost etchings, is always transparent or opaque water ice.
The ice pictures form in rather an exclusive fashion, and two types never intrude upon each other’s territory, although we often find both types upon one pane of glass, as shown in the photographed illustration Nos.140aand140b.
The ice films always begin to develop upon the colder portions of the glass first. Feathery plume-like designs form first upon shaded portions, and slowly follow the fading sunlight as it passes from one pane to another, until the entire window is often covered with these transparent ice pictures. During zero weather the feathery types thicken to an astonishing degree, more so than the opposite type, or arborescent ice film.
Another type of ice formation, and an interesting one, which in the photograph resembles somewhat a vegetable root or growth, is a form of ice which develops and grows upon and under peaty soil. These singular little ice columns rise as by magic, and form a miniature forest of tiny ice columns; frequently raising upon their tops the soil, stones, etc., to a height of many inches.
126. Local storm type
126. Local storm type
127. Cold high altitude
127. Cold high altitude
Nos.145,146and147, show photographed examples of this type of columnar ice,No. 147being a largely magnified section of one of these tiny columns in detail. Icicles are another interesting phenomenon belonging to ice study. They are evidently produced by the thawing of snow, and we frequently discover “freak” icicles hanging pendent from the house eaves during a thaw. They are, in a way, one of the many mysteries pertaining, and to be classed as ice crystallisations, and are closely related to the wonderful stalactite formations found in deep caves.
Beautiful beyond powers of description are the magical, fairy-like scenes which follow the passing of a great ice-storm. If you are out of doors just after such a storm, when the first rays of the sun begin to shine forth, lighting and touching every ice-sheathed twig with gold, and before the ice has begun to melt and fall from the trees, you can well imagine that you are catching a fleeting glimpse of fairyland! Trees that before the storm waved their leaf-stripped branches, bare and unlovely, in wailing symphony, tuned by the bleak wintry blast, have suddenly been clothed anew and made beautiful for a brief time, by their silvery coating of ice. Each tiny twig glitters and scintillates and crackles beneath the pale wintry sunshine; beautiful beyond words to picture.
These ice-storms occur more frequently in January, and are usually followed by a warm wave. They are seen in all their beauty in the New England States. Frequently after such an ice-storm there is a noticeable swelling and expansion of twigs and buds; the first suggestion of verdure and an early spring.
It is intended in this article but to touch upon the simple structural formation of the ice. There are still many important facts to discover, many interesting problems to solve. It would be interesting to know why the ice crystals which originate and have their being in the same body of water, and under precisely the same conditions of temperature vary so greatly in their structural formation.
128. Germ or birth of ice crystal
128. Germ or birth of ice crystal
129. Discoidal ice crystal. Second stage in which crimps begin to appear around the edge of disc
129. Discoidal ice crystal. Second stage in which crimps begin to appear around the edge of disc
130. Third stage of development. Scallops well defined
130. Third stage of development. Scallops well defined
Ice crystallisation in all its branches is a fascinating and wonderfully instructive study. It is still in its infancy, there is much as yet undiscovered material for experiment awaiting both the student and the camera specialist.
“Sometimes it was simply smooth and clearFor the gladness of Heaven to shine through, and hereHe had caught the nodding bulrush topsAnd hung them thickly with diamond drops,That crystallised the beams of moon and sun,And made a star of every one:No mortal builder’s rare deviceCould match this winter-palace of ice.”—Lowell.
“Sometimes it was simply smooth and clear
For the gladness of Heaven to shine through, and here
He had caught the nodding bulrush tops
And hung them thickly with diamond drops,
That crystallised the beams of moon and sun,
And made a star of every one:
No mortal builder’s rare device
Could match this winter-palace of ice.”
—Lowell.
131. Fourth stage, flower-like shape beginning to show
131. Fourth stage, flower-like shape beginning to show
132. Ice flower completed
132. Ice flower completed
133. Flower-like shape fully formed
133. Flower-like shape fully formed
134. Ice flower beginning to show shadings
134. Ice flower beginning to show shadings
135. Ice crystals growing downwards into the brook
135. Ice crystals growing downwards into the brook
136. Group of ice crystals. Observe how in growing they avoid other
136. Group of ice crystals. Observe how in growing they avoid other
137. First stage. Lance-like form seen pushing out from banks of brooks
137. First stage. Lance-like form seen pushing out from banks of brooks
“We knew it would rain for the poplar’s showedThe white of their leaves, the amber grainShrunk in the wind and the lightning nowIs tangled in tremulous skeins of rain.”—Aldrich.
“We knew it would rain for the poplar’s showed
The white of their leaves, the amber grain
Shrunk in the wind and the lightning now
Is tangled in tremulous skeins of rain.”
—Aldrich.
Fickle April, the season of sunshine and rain, comes on apace; and the bluebird, that “comes first you know, like a violet that has taken wings,” has piped his clear advance notes in the hedges, and a bright message of promise his cheery song always brings, of blossoms and verdure soon to follow.
Surely each changing month brings with its advent its own peculiar charms. The seasons of frost, snow and ice are full of beauty to those of us who have looked into, and delight to ponder over, the many secret ways of nature. But April with its sudden showers, which eventually do bring forth the May flowers, we hail with hope; and are only too happy to leave behind us, as a pleasant remembrance, the more sombre, frozen charms of winter.
The ice-bound brooks have at last burst their fetters, in the meadows by the little streams the stems of the willows are yellowing, and here and there the pussy willows, in their silver, furry coats, are bursting forth; the alders have sprouted, and from the ooze of the marshes the swamp-cabbages are pushing forth their sharp-pointed purple sprouts. While the honking geese, flock after flock, trail wedge-like in the early mists of the morning, across the gray skies. In the sedgy places where the flags are just sprouting the “peepers” at twilight begin their spring chorus, and with the advent of all these signs of advancing spring, we realise that the “backbone of winter” has fairly been broken, and the earth is preparing and waiting for April, with its beneficent showers to bring new life into all dormant buds and vegetation beneath the earth and to arouse them once more from their long winter’s lethargy.
138. Second stage of lance-like crystal
138. Second stage of lance-like crystal
139. Lance-like form completed
139. Lance-like form completed
140. Freak ice crystals
140. Freak ice crystals
140 b. Group of ice crystals containing germs, “freaks” and one completed ice flower
140 b. Group of ice crystals containing germs, “freaks” and one completed ice flower
“April cold with dropping rainWillows and lilac bring againWith the whistle of returning birds.”
“April cold with dropping rain
Willows and lilac bring again
With the whistle of returning birds.”
Since the rain plays such an important role in nature’s plans, certain facts concerning its origin, and the clouds which govern its formation and fall, will prove of interest.
The prior causes of rain are due to the evaporation of moisture which is constantly going on, from ocean, lake and river, and all vegetation; until the air is freely saturated with moisture thus evaporated. Then “Mother Nature” assists, causing turbulent, driving winds to rise, and all her elements combine forthwith, to precipitate the moisture; and then follows the rain.
The rays of the sun falling upon the air stratum nearest the earth cause it to arise and expand. Thus, as a result, the clouds are formed. The ascending air leaves a partial vacuum below, which causes surrounding air to rush inward; which in turn causes winds. Once this process starts, it tends to grow and perpetuate itself. The inrushing air below forces the rising air still higher and higher, which causes dense clouds to form and rush upwards to great heights. Both snow and rain fall as a result of warm moist air being forced upward to a great altitude, and its moisture condensed.
The smaller raindrops fall from the lower cloud strata, but the larger drops descend from a much higher altitude. In the higher, frigid altitudes where snow, and the granular snow pellets are formed and exist, in the upper sections of the clouds; by falling down through the vast cloud regions below, they gradually collect minute cloud particles, and smaller drops in their travels, and thus, by melting, as they encounter warmer air currents, form the very large, high-altitude raindrops.
141 a. Coral-like branch showing the “feather type” in detail
141 a. Coral-like branch showing the “feather type” in detail
141 b. Window-pane ice. Two forms, the arborescent and feather types
141 b. Window-pane ice. Two forms, the arborescent and feather types
It has not until quite recently been possible to measure with any degree of accuracy, and photograph raindrops in the exact size in which they fall. But now that it has become possible to do this, it is most interesting to know the process. It is also most important to be able to know that certain types of raindrops fall during given storms. For instance, a very large type of raindrop emanates from a violent thunder-storm, when there is vivid lightning. Another distinct type belongs to the general storm, and there are many others, their form and size being governed entirely by the clouds and the character of the storms from which they fall.
Hundreds of samples of raindrop impressions have recently been secured, and the method employed to collect and photograph them is most unique. To secure these raindrop impressions, emanating from various storms and clouds, a shallow tin receptacle about four inches in diameter was used, the bottom of the tin being covered with fine, uncompacted flour an inch deep. The flour was then exposed to the rain for about four seconds, and the raindrops allowed to remain in the flour until each drop had hardened as it fell. These dough pellets, or raindrop impressions were found, in every instance, to correspond very closely in size to the raindrops as they fell. When thoroughly dried out they were carefully removed from their bed of flour, labelled and photographed. This method of determining the relative dimensions of raindrops which fall during various types of storms, has proven to be the most satisfactory method as yet discovered.
142. Beautiful type of window-ice growing like delicate sea-weed
142. Beautiful type of window-ice growing like delicate sea-weed
143. Window-pane ice. Resembling pampas grass
143. Window-pane ice. Resembling pampas grass
144. Another type of window-pane ice
144. Another type of window-pane ice
The large raindrops are invariably great travellers. The larger the drops the greater the height from which they fell. Some of them travel a distance of five to eight miles before reaching the earth.
Raindrops falling from very high altitudes invariably start out as snowflakes, as the upper section of a rain-cloud, when formed in the high frigid altitudes, is usually composed of snow. The general rain-storm usually furnishes small to medium-sized drops. But sudden thunder-storms, where the clouds gather in dense, mountain-like formations, as the one shown in the photographed illustration, furnish the very largest raindrops which fall, unless we except those which may sometimes result from the melting of large hailstones, which emanate sometimes from very violent storms of the whirling, tornado type.
The cold gray rains of early spring, which frequently turn to ice in falling, and sheathe the branches of trees with a glittering coat of icy mail, change in character as spring and the warmer weather advances.
The mid-summer thundershower is still another type, and an impressive one. When all nature lies gasping and parched under the withering heat of a torrid sun, when the pebbly beds of the little streams are brown and dry, and the thirsty cattle low plaintively in the sun-scorched pastures, then suddenly, the south winds send a long-drawn, whispering sigh through the motionless tree-tops; the poplar leaves begin to tremble and toss, and faster and faster the thunder heads begin to roll up and assemble, and rush together, with low ominous mutterings.
The clouds, coppery-hued and black, and full of menace, hang low, and almost seem to touch the hills, rising winds chase each other and catch up stray dead leaves and débris, sending them whirling and dancing in fantastic eddies; while the startled swallows wheel low before the rushing, mighty tumult of the approaching storm.
145. Another example of Columnar ice. Formation like vegetable roots
145. Another example of Columnar ice. Formation like vegetable roots
146. Columnar ice, found under peaty soil
146. Columnar ice, found under peaty soil
147. Columnar ice, section shown in detail, largely magnified
147. Columnar ice, section shown in detail, largely magnified
Nothing can compare in grandeur, to the marshalling of Nature’s forces together and the raging fury of a great thunder-storm. Truly the roar of the thunder may well be likened to Heaven’s artillery, and no pyrotechnic display ever equals that which the jagged, forked lightning creates amid the inky, ominous clouds of the heavens. And then the finale; the low, distant, retreating growls of the passing thunder, the gradual lifting of the clouds, and then like magic, their leaden, ominous curtains are swept aside, and the happy sunshine is with us again, and the earth, refreshed and purified by the grateful shower, gasps no more in the throes of heat.
And how lovely is nature after such a shower. How sweet and fresh the air, and how each blade of grass, and all vegetation sparkles and scintillates anew. The little mountain torrent which trickled so listlessly, just a mere silver thread among its mossy stones, has gained new courage and strength since the shower, and its gurgling may plainly be heard as it now rushes madly down the incline. The meadow brook has overflowed its banks, and formed a miniature lake, in which the grateful cattle stand contentedly knee-deep. All the birds rejoice, and the robins, noisiest of them all, pause to plume afresh their wet feathers, and pipe their peculiar rain song; a distinct note of gratitude and joy for the coming of the rain.
The rain, besides playing a most important part in aiding all vegetation, is an acknowledged and powerful agent in the cleansing and purification of the atmosphere. Foul air is dissipated, and dust and particles which rise in clouds and permeate the air we breathe, are beaten to the earth and dissipated by the kindly rain.
148. Very great thunder-storm drops
148. Very great thunder-storm drops
149. Rain from high cirro-stratus clouds
149. Rain from high cirro-stratus clouds
150. Rain from low nimbus clouds
150. Rain from low nimbus clouds
Storms which arise in pleasant summer weather are frequently caused by the diurnal breezes which ascend mountain slopes causing sudden clouds to assemble, and thunder-storms to follow. Violent thunder-storms are caused by the intensely hot air which arises from the earth in summer, and which encounters the cooler air descending.
Frequently “heat lightning” may be observed flickering fitfully in the skies, when there is no rain. When such is the case, you may be assured that a storm cloud hovers somewhere in that direction, although it may not be visible, or its thunder audible. Whenever the lightning is brilliant and continuous the storm is sure to be of a violent character, when frequently the destructive bolts are fifty miles away.
The rainbow, that wonderfully beautiful bow of prismatic tints, which sometimes throws its ethereal arch across the heavens for a brief while, is caused by the reflection of the sun’s rays shining upon drops of rain, the colours being arranged in definite order; red, orange, yellow, green, blue, indigo and violet. The lunar rainbow, which occasionally forms at night when the moon shines, is not of frequent occurrence, but very beautiful when it does deign to show itself. Its colouring is not nearly as distinct at the rainbow, but ghostly, and of a pale-yellowish tint. Frequently a double rainbow is seen after a shower; this is but a reflection of the rainbow proper, but indescribably beautiful.
In the coming of the rainbow we have a Biblical symbol. It is spoken of in Genesis, and was used as a token of the Covenant; as a Divine promise to man, that the earth should never again be destroyed by flood.
There are numberless so-called signs, which are considered reliable indications of rain. Almost invariably a continuous south wind will, in most localities, bring in its wake rain in a few days. On the contrary, a continuous north wind is liable to dispel all rain signs for a time.
151. Thunder and hail storm type
151. Thunder and hail storm type
152. From a great rain storm which lasted 15 hours
152. From a great rain storm which lasted 15 hours
A “mackerel sky,” that is, a sky covered with a wide expanse of small silvery clouds, round in shape, is another rather sure indication of rain; salmon-coloured, leaden, or silvery clouds are usually indications of falling weather, and when at sunset the clouds of the west are brightly coloured, red or flame-coloured, afterwards followed by lighter hues, streaking up from the place where the sun disappeared, and stretching far across the sky, finally converging to a common point on the opposite horizon, you may be quite certain that somewhere within line of the sun, there is a heavy storm brewing; although it may be invisible, and hidden by the earth.
We know that in certain parts of the earth the rain seldom falls. In Lima (Peru), Thebes (Egypt), and in certain sections of North Africa they very rarely have rain. The presence of forests tends to increase the rainfall. Over the ocean it is always clear when the trade winds are blowing steadily, while rains fall continuously in the zone of calms.
Some countries are rarely free from rains; in Hindustan, Brazil and Guadeloupe the rain is almost continuous, while certain localities are noted for prolonged seasons of either drought or rain, which occur at stated periods, as in California.
The benefits derived from the rain are unlimited. After the visitation of a great and prolonged drought, when lakes and rivers and their many tributaries, the little mountain torrents which feed them, are dry for lack of rain; when the gardens and all vegetation at last succumb and shrivel for lack of moisture; when we really endure great bodily privation, and domestic animals suffer for lack of water, then we may realise fully, what a wise and necessary provision the rain is to us.
153. Thunder cloud
153. Thunder cloud
154. Nimbus or low stratus clouds
154. Nimbus or low stratus clouds
It seems therefore that there is always a great promise and hope embodied in the providential falling of the rain at such a crisis; nothing can express the thought I would convey more clearly than the following beautiful lines:
“Hast thou forgotten God who gives the rain?Plentiful and merciful the long showers pourOn parching field where dust and drouth were sore,Yet, will thine eyes watch out the night again?
“Hast thou forgotten God who gives the rain?
Plentiful and merciful the long showers pour
On parching field where dust and drouth were sore,
Yet, will thine eyes watch out the night again?
“What hope had earth gasping at yesternoon?What hope hast thou whose comfort shall be soon.To-morrow where the upland fields lay black,Thou shalt go forth and look on life come back.Harvest shall follow seed-time yet again.Hast thou forgotten God who gives the rain?”—Earle.
“What hope had earth gasping at yesternoon?
What hope hast thou whose comfort shall be soon.
To-morrow where the upland fields lay black,
Thou shalt go forth and look on life come back.
Harvest shall follow seed-time yet again.
Hast thou forgotten God who gives the rain?”
—Earle.
THE END
Endpapers
Endpapers