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About The west shore. (Portland, Or.) 1875-1891 | View Entire Issue (Oct. 1, 1879)
October, 1879. THE WEST SHORE. ant at Penewawa ferry, as the stage driver testifies, between one and two o'clock p. m., when he left the hotel and drove up the canyon. Suddenly the sky clouded over, and the storm burst on the hills soon after he passed. The ocean w ind from the west, laden with its invisible vapor, met the mountain winds sweeping down from their cold, snow-clad summits, into the warmer basin below, forming circuits of greater or less extent, cooling air and vapor, producing mists and cloud masses, roll big them onward in vast whirls, grow ing colder and colder, until the air, un able to hold up its enormous burden of vapors rushing together like waters in a funnel, let the mighty mass drop upon the nearest and coldest hills. A very intelligent gentleman, who was traveling in Southern California, near Arizona, in 1878, describes a water spout which he witnessed about mid day in that hot and treeless desert. It was in early summer. The mercury stood over 1000 Fahrenheit. Not a cloud or wisp of vapor visible. The ground was parched. The air was sul try and oppressive. The first notice of change was a cloud-speck moving rap idly, enlarging, overcasting the sky, whirling in great volume until it poured an immense quantity of water from its inverted, cone-shaped reservoir, scatter ing and almost drowning a camp of In dians in its path, and filling the valley with its torrent. In an hour it was all gone. The sun shone out again, and soon the earth became dry and parched as before. Its phenomena is explained by the sea wind and told mountain wind rush ing towards the same heated basin, like cold air from various quarters into a hot room, forming a eiicuit, converging to a focus, condensing the invisible va por into cloud mist, ami then into tor rents of rain. This lesult i liable to occur in every heated basin, rimmed by a chain of high, cold mountains. On broad plains or prairies like those of the Mississippi and Missouri valleys, the rushing air currents take the form of tornadoes. On the ocean they appear in the vaster sweep of hurricanes, with winds con verging to the center of the storm, roll ing up the mountain waves, amid the w ildest gleams of lightning ami crash of thunders, and downpour of torrrnts of condensed vaxirs. Heat is the one cause of the ascent of those invisible vajHirs, and neat is tne one cause ot the rush of winds from all directions to the heated centre, cooling and condensing those vapor-lnden winds, producing dews, fogs, gentle rains, violent storms, tornadoes, w ater-souts and hurricanes. Prof. Hrocklesby remarks that, It is by no means uncommon for several walei-spouts to appear at the same time. In May, 1830, Lieutenant Ogdeu beheld, on the edge of the (iulf Stream, no less than seven in the course of half an hour; varying in their distance from the ship from two hundred yards to two miles." lie adds: "It is a common belief, that water is drawn up by the action of the s font into the clouds; but there is no proof whatever, of a continuous column within the whirling pillar, and the fact that the water which some times falls from a spout upon the deck of a vessel at sea, is always fresh, sufli ciently refutes the idea. The torrents of rain, by which this phenomena is often accompanied, can be fully ac counted for by the rapid condensation of vapor that occurs when the warm humid air of the sea flows inward to the vortex of the whirl, and there com bines with the cold air of the uper re gions of the atmosphere, which descends to fill the partial void." Prof. II. also remarks that : Rain is firoiluced by the rapid union of two or more volumes of humid air, differ ing considtrably in temperature; the several portions in union being incapa ble of holding the same amount of moisture that each can sparally re tain. This circumstance results from the law, that the capacity of the air for moisture decreases at a faster rate than (he temperature. "This edict may be thus illustialcd: si cubic inches of air, at the tern I h t .it ii r t- of 'J.- Kali., can contain no more than 1,1 grains of moisture, and an equal volume, at (J- Fah., only 7 ' grains. Now, if the two volumes are mingled together, thrir average teiiiK-raturc will lie y) Fahrenheit, ami the w eight of moisture they united ly possess w ill I yj) grains. Hut, at this triii)craturc, 31 -t grains is all the moisture that Kxo cubic inche of air can possibly retain; since the first por tion, by its union with the second, di miaitbod its caparity ont-kalf, while thai of the lajttcr was only doubled. The excess, therefore, of 77, grains will be condensed, and descend in the form of water." This plain statement of the examples and the law of the condensation of va pors in the air, found in Prof. Itrock lesby's Elements of Meteorology, (A. Di iH.),) pages 7i-., agree with the facts which we see in the dews, fogs, clouds, sluiwets, storms, and water spouts. His estimates of the iower of the air to hold invisible vapor, and of the law of condensation, published in 1849, agree with the tables published by Dr. F. Smith, of London, published in 1873, and re-published In New York in (876 K X A MI'I.K. The following example of the effect of a water sjioul in Los Angeles county, Southern California, Is given by O. P. Sites, Kmj. : In the San Fernanda valley - about twenty miles long and ten miles wide the torrent of water from one water spout, or cloud-burst, as it is often 1 ailed, tore a channel, or ravine, about twenty or thirty feet deep and one hun dred feet wide nearly the whole length of the valley. Dr. lluibank, who had a sheep ranche covering a iortlnn ol the valley, could not cross to his near est Hock for aevtral days, on account of this torrent. It soon ran dry a liefore, leaving this longdeap gulch as witness of Its force in cutting away the valley. This vast amount of waterfall BOOB that dry plain la proof of the greater amount suspended In that heated air, ami liable to be condensed at any time by the chilly mountain winds meeting the v ap.11 laden ocean winds. Such an example Is also In proof of the value of grain fields, vineyards, or chards, shade trees ami limber grove as slow condenser of moisture, pro ducing dew, mists, shower and regu lar annual harvest. AMOUNT or w.MKN Ntf.P i v a roil ANt 1 1 Mil TO iiNIKNATIOK. According to thrc table a column of air ten feel square, ifrel high, saturated at Ma Fahrenheit, contain it gallon. The tame column, 5xw feet high, intalns it gallons. A col umn covering an acra, imo feet high, at JJ, hold, if saturated, i,h" gat Ion; ami the same minimi, , fett high, hold 7o gallon. A column ten frit squjie and 1 fr ft high.