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VIII. RAINFALLS.

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this chapter being devoted to rainfalls, a few introductory observations may be in order. the essential need on earth’s surface for growth of vegetation, and the sustenance of life, depending thereon in some form, is in universal irrigation, which nature failed to furnish by its internal provision of water with its outflow of springs and lakes, except by artificial use. the rainfall on the earth is no more intended for filling of springs, lakes and seas than it is for supplying us with fuel. it is simply a provision for surface watering of vegetation, and has no more effect on the existence of living springs and subterranean outflow of water than the eclipse of the moon. there never was a rainfall, except, perhaps, in noah’s time, that wet the general surface of the country to the depth of three feet, and rarely one-half of that. it is generally called a good, soaking rain that moistens the bottom of[45] the potato hills, and to wet what the soil will hold one to two feet requires a prodigious amount of water. it is claimed by proprietors of orange groves that a volume of water of six inches in depth is requisite to thoroughly irrigate the grove. if the claim that rain has no effect on the supplies of springs and lakes be true, you will ask why it is that after a long drouth and a heavy rainfall, the springs resume running, and water returns into wells that have for a time been dry? the effect on those sources of supply is simply the same as results from wetting a sponge to take up water which will not absorb and be taken up in a dry one. you can easily be convinced of this effect. to show that water will run uphill or away from the earth: the surface of the earth becoming saturated, and in some places penetrating into the seams and crevices of rock and soil, at once forms a medium of attraction for the waters below to follow. another valid reason is the general condition of the atmosphere from the time of drouth to a condition of moisture when it becomes really a mammoth sponge after being dampened. against the claim that rainfall has little or no influence in raising or producing springs or lakes, or living wells, this question naturally arises regarding springs, which has in a measure been answered. it is, however, a pertinent[46] question, and a pleasant one to answer fully.

in the summer season, most commonly of any, the air becomes hot and dry. the surface of the earth loses the moisture of the air’s influence, together with the sun’s heat evaporating the dampness, becomes generally arid, and fails thereby to be a conductor of the moisture from below.

as a season of very dry atmosphere occurs for months at times, the soil becomes correspondingly dry and dusty to quite a depth. from this cause the springs and water in wells recede and sink away. it is an easy matter to find people who have witnessed the following seeming phenomena in times of drouth: after a period of weeks or months of drouth before any rainfall has occurred at all, the fountains, long dry, often commence to run, and wells begin to fill with water, and this without a drop of rain.

just here comes the pleasant task of answering the question fully: how can this occur without a soaking rain?

at such times, when the earth and all nature is thirsting for water, and every fountain seems to have dried up forever, the day will come which will bring these evidences.

the aged will complain of their rheumatism;[47] men’s bones will ache; geese will wash in the dust; the peacock will scream; birds, beasts and vegetation will feel a humidity in the air and intuitions that rain is near. as the atmosphere has felt the approach and preparation for rain some time in advance, so all nature feels its effects. to illustrate the burned or dry condition of the air, you may consider this test: take a pail of water, and a dry sponge, big as your head, and lay the sponge on the surface, and it will take a long time for the sponge to absorb the water and become fully saturated. wet the sponge before the test and squeeze it dry as you can, and lay it on, and it will fill rapidly and quickly. pour a pail of water on the floor and try the same experiment. your sponge will not fill at all if dry, only a little as it comes in contact with the water; but moisten it as before, and press it nearly dry, and throw on the puddle of water, and it will drink itself full at once, drawing up the water like a pump. you cannot wipe up a floor with a dry sponge.

the springs and wells that have dried and receded a short distance from their usual level from lack of moisture in the air that penetrates the surface, quickly feel a returning moist condition and are drawn by the same influence upward[48] as the water climbs up through the damp sponge.

the atmosphere performs the same duty as the sponge, and this answers why the springs and wells resume running before a drop of rain has fallen, and which, when it comes in copious quantities, still adds to the general effect of making a stronger draft on the fountains below.

another question proper to ask scientists is this: if the rainfall affects springs and lakes, how is it that the analysis of mineral springs in all quarters of the globe is not affected by every change of season? how can the waters of saratoga, carlsbad, waukeska, kissengen or of any other such spring be relied on for uniform assays? how can this great variety of springs come in such near proximity to each other and possess such distinctive curative properties as at saratoga, for example? within a radius of two or three miles are springs, one of which is a cathartic, another a diuretic, another emetic, another tonic, and so on, no two alike, but retain their individuality through all times, wet or dry? they are affected only in amount of flow by the same atmospheric conditions of either dryness or moisture, as just described.

when the atmosphere is heavily charged with moisture, it becomes a mammoth sponge, and[49] this condition of air, evidently, is what precipitates thunder showers in the summer. as all the hills and mountains are the result of water upheavals, they are for this reason the reservoirs of water for watering the earth, and therefore quicker to respond to atmospheric conditions than the plains.

it is almost without exception that thunder showers form their nucleus on the heads of mountains and the tops of hills.

after a shower let us see the condition and results. the face of nature smiles after its refreshing wash; every tree and plant has drunk its foliage full of new life; the air’s sultriness has changed to freshness. all animated life seems to take a fresh lease, and as the clouds roll away and the quickly swollen streams rush to the rivers, lakes and oceans, it seems as if almost a deluge had passed by.

the remarks, “what a lovely shower!” “what a much needed rain!” “what lots of good it will do!” etc., pass between neighbors. farmer smith comes along and says, in reply to the shower being such a cracker, that he went into his garden to set out cabbage plants, and down little over an inch the ground was dry as powder; that while this will do lots of good to grass,[50] and “sich,” it wants a good soaker to get down to the bottom of the potato hills.

such is the history of most of our copious showers that flood everything for half an hour, but not a drop reaches the roots of forest trees of any depth, or does anything more than to temporarily wet and freshen the surface.

such being the case on the prairies and unbroken plains, the evaporation of two or three days’ sun leaves them in almost the condition of a desert. this was the case in our new states, nebraska, kansas, colorado and indian territory, which, now so productive, were, as our early geography describes them, before the soil was broken to hold the rain for a while, the great american desert.

on a hot day the air in the valleys is still and suffocating. climbing up from the valley to the hill or mountain tops, you find a cool and refreshing breeze; the moisture in the air is becoming condensed. here is where the philosophy of lightning seems to work a prominent part. the cold currents of air and moisture, collecting, seem to come in contact with this subtle and wonderful agent, and the result is like fire to powder, a vivid flash and explosion. stand on the plain on a sultry day and watch that little white crest of what we call a[51] thunderhead. the farmer who has hay down will notice it with a little anxiety. the sailor will think of his sails, and the picnickers will think about going home. soon a flash, and a dark base is forming. soon the rumble of thunder is heard; the girls with their bonnets on begin to look worried. the captain on his yacht is giving orders to reef sails, and farmer jones and his boys are cocking and pitching hay for their lives.

the little white-capped clouds of an hour ago have turned into a black and threatening massed park of artillery. every discharge deepens and darkens the advancing column.

just as the vessel’s sails are dropped and snugly reefed, just as the farmer rushes his team, with load of hay or grain, into his barn, and the picnic is almost under cover, the big drops of rain begin to patter. another flash and quick report; a scream from the girls, nearly as sharp, and they rush for shelter, and down comes a torrent of rain.

a slight cessation, another flash, and, like shaking a tree of fruit, every electrical explosion seems to shake down a fresh reserve of rain drops. this is in keeping with the theory that after great battles the cannonading produces a copious rainfall.

[52]it is a method at times adopted by military garrisons when destitute of water, when the atmosphere is in a favorable condition for rain, to get out a battery of artillery and have a season of vigorous firing, and generally with successful results.

and while all this grand and complete arrangement supplies vegetation with its bathing and drinking, as said before, it has nothing to do with the living and lasting supply of our springs, lakes and rivers. they are fed from a never failing and almost unchanging source—that is, by the immense supply taken in at the polar holes in a river over 4,000 miles wide at each end of the earth’s axis.

that the presumption of rainfall furnishing the supply for all of our lakes, springs and wells has never been questioned seems almost discreditable to the observing talent of our age. whatever the character of rainfall, either by protracted storm or sudden and copious showers, it cannot escape our notice that the largest portion of the water runs from the highlands to the lowlands into the gulches and small streams, and thence to the rivers, into the ocean; so that the percentage of water retained by the soil is much smaller than that which runs away.

in our western prairies, the country formerly[53] called the indian territory, the soil was covered with an almost waterproof matting of grass roots, on which, when showers fell, the penetration was so slight that in a very few days evaporation left them parched and dried. since the settling up of our territories, which were once termed deserts, the soil has been broken by the farmer’s plow, thus admitting the rainfall to be longer retained in the surface soil, which fact has led to the development of lands once considered barren to become some of the most fruitful grounds in our domain.

another peculiar feature of climatic change may be mentioned here, whereas until recent years thunder showers and storms were almost unknown in many of our western states and in the pacific states also, till now these storms and showers, with their electrical disturbances, are nearly as common as in older states.

another feature of weather which has seemed to develop in recent years is that of milder winters in our northern states and colder freaks in the southern; snows and frosts reaching states which rarely ever had such experiences, and the burdens of snows becoming much less in states which always expected a long season of sleighing.

it is proposed to venture the following reasons[54] as conducive to much of this change in weather conditions of the country at large. first, the general denuding of our forests, which evidently has much influence on the water courses. next, the settling up of the whole country, and location of cities and towns from ocean to ocean, all quite evenly distributed, and in a great portion of them large amounts of machinery, composed of iron and steel, producing a great amount of friction and electrical influence in their workings; besides the almost innumerable fires from furnaces, factories and households, discharging their heat into the upper air. again, the railroad system, with its millions of tons of steel rails, make a magnetic connection between every state and almost every county in forming one grand combination. the rush of thousands of trains all over the country, with their friction by wheels on the tracks, and the rush through the atmosphere, cannot fail to influence in largely equalizing the same. still another potent influence must exist in the almost unlimited number of wires for telephone and telegraph purposes, which make all the electrical combinations more complete than anything else. if all these things combine, it does not seem strange that magnetic and electric currents and conditions of our weather throughout the country should be somewhat modified.

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