Page:Popular Science Monthly Volume 24.djvu/153
is recent. The inundations by which the lower country is frequently submerged come from the Poyang Lake, concerning which very little is actually known, either as regards its floods or its rain-falls. It is known only that there is evidence of a great thinning out of forests on the mountains of Southern Kiangsi, although it has not been carried to the extent that Che-kiang has experienced, where arboriculture is systematically pursued to meet demands for timber. In the hills near the coast, which are stripped annually of grass, ferns, and bushes for fuel, the process of the gradual denudation of the hills is distinctly observable. The soil is never carpeted by leaves; no humus forms; rain, instead of slowly percolating as through a sponge, rushes in water-courses as from the roof of a house into gutters, speedily filling them, and carrying with it soil, which tends to increase the evil. In this way the lakes are destined to become desiccated much sooner than they otherwise would be. It is because of the occasional sudden rush of waters that freshets are always attributed to the spouting of chias—subterranean monsters. Several of those are reported as being concerned in the late floods. While there is conclusive evidence that there has been in recent times a great destruction of forests, it is not clear that floods have proportionately increased in number or rapidity; it is, however, what might be expected, and it is what is affirmed by natives when accosted on the subject. Deforestation has had one favorable effect in the south of China, in reducing the ravages of jungle malaria, which recedes with the advance of agriculture.
New Serviceable Metallic Alloys.—Three new metallic alloys have been recently introduced, which seem fitted to serve as substitutes for bronze, imitation gold, and imitation silver. Delta, a bronze made by Mr. Alexander. Dick, of London, is a compound of iron, zinc, and copper, the proportions of the ingredients being varied according to the color it is sought to obtain, and has the advantages of extraordinary tenacity and flexibility. It can be beaten, and forged, and drawn when cold, takes a perfect polish, and, exposed to the air, is less liable to tarnish than brass. Aphthite is a "gold," which does not change, and is composed of eight hundred parts of copper, twenty-five of platinum, and ten of tungsten. Its shade of color may be changed by varying the proportions of its constituent metals. Sideraphthite is a similar "silver" metal, and is composed of sixty-five parts of iron, twenty-three of nickel, four of tungsten, five of aluminum, and five of copper. These alloys are capable of resisting hydrosulphuric acid, are not attacked by organic acids, and are only slightly attacked by inorganic acids.
Mr. F. H. King, State Geologist, estimates the bird population of Wisconsin at sixty-six per square mile, or 3,565,000 for the State. Each bird is assumed to eat fifty insects a day, or 6,000 for the summer. Hence all the birds will consume 21,884,000,000 insects a year. "Add to this amount the work which these birds do in their Southern homes, and we have a low estimate of the influence they exert over insect life."
An improvement on the Bunsen cell, by M. Azapis, consists in substituting for the acidulated water a solution of about fifteen per cent of cyanide of potassium, caustic potash, common salt, or salammoniac. The intensity in the new form is as great as in Bunsen's, and the advantages are, greater constancy, less waste of zinc, and very little smell; further, the zinc does not need amalgamating.
H. T. Cresson has obtained, from Aztec clay flageolets, the fourth, seventh, and octave tones of the diatonic scale, and the additional sounds or semitones which constitute the chromatic scale. These notes are produced by means of the four finger-holes and by stopping or half stopping the bell of the instrument. The flageolets are pitched in different keys, and, if the Aztecs knew the full capacity of their instruments, their music must have far surpassed that of other uncivilized peoples.Professor Archibald Geikie remarks, concerning the future history of the Grand Cañon of the Colorado, that it has still about a thousand feet to remove from the bottom of its channel before its slope will become so slight that its erosive power will nearly cease, and that it is conceivable that, should no geological revolution occur in the region, the canon may still be deepened to that amount. There are indications, however, that a limit maybe set to the possible depth of the chasm. As in the "creep" of a coal-mine, the bottom of the cañon, relieved from