  “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 139. Lance-like form completed 140. Freak ice crystals 140 b. Group of ice crystals containing germs, “freaks” and one completed ice flower “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 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 143. Window-pane ice. Resembling pampas grass 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 146. Columnar ice, found under peaty soil 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 149. Rain from high cirro-stratus 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 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 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 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. THE END Endpapers Endpapers
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