Page:Popular Science Monthly Volume 2.djvu/397

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9. The downward current of the Alpine streams generates motion in virtue of their mass, and of the space passed over during their descent.

10. This mass-motion, when temporarily checked by any resisting object, is converted back into heat.

11. Man arrests a portion of this motion by means of a large water-wheel, and, by the aid of a crank and a connecting-rod, transmits the motion to the piston-rod of an air-compressor.

12. In compressing air, we accumulate motion as a force or tension; and the compressed air yields this force again without loss (exception made of the loss occasioned by the friction of the piston, which reappears as heat).

13. Compressed air—a storehouse of motion—is made to pass into a contrivance similar to the steam-chest of a steam-engine, where a sliding-valve forces the air to enter alternately above and below the piston to which it thus imparts common mass-motion. The process is the same as the one operating in the steam-engine, with the difference that the motor agent is compressed air in place of steam, and that the motion is ultimately obtained, not from the combustion of fuel, but from the descent of water.

14. The mass-motion of the water, now transferred to a drilling-machine, is modified by means of mechanical contrivances in a manner such that powerful blows are dealt in rapid succession upon the cutting-tool which drills the hole; mass-motion is thus converted back into heat.

15. The drill-hole is filled with a mixture of substances containing chemical motion, which, at any time, may be given out as heat and mechanical motion. By the ignition of the mixture, new combinations of substances occur, which, owing to the new distribution of chemical motion, take up a much greater space, and thereby split the rocks.

16. Mont Cenis Tunnel (as will be the future one of St. Gothard) was bored by the sun's heat.—Mohr, translated by Hotze.


Cinchona in Bengal.—In 1862 Dr. T. Anderson began the cultivation of cinchona (the tree that yields the Peruvian bark) in Sikkin, Bengal. The venture has proved profitable; and at the present time he has under cultivation cinchona-trees of three species, to the number of 1,707,115, yielding about 300 pounds of bark per acre. Besides these, he has 480,000 young plants in nursery.


Bulb-Culture in Holland.—Although one-fifth of the entire land in the Netherlands is worthless for cultivation, and another fifth is meadow-land, yet 47,500 acres of the remainder are devoted to tobacco, 35,000 to hemp, and 500 acres to raising tulips, hyacinths, and other flowering bulbs. Holland has ever excelled in this sort of horticulture.


Antiseptic Properties of Borax.—A paper by M. Jacquez on the preservative action of borax and the sub-borate of ammonia, on animal matter, read before the French Academy of Sciences, gives an account of some important experiments made by the author during a period of five years, with a view to ascertain the antiseptic properties of the substances named. In June, 1853, he dissolved 25 grammes (about 387 grains) of gelatine in 100 grammes (a little over 3 ozs. of water) with 4.50 grammes—nearly 70 grains—of borax. The mixture remained in an open flask all through the summer, without any sign of mould or putrefaction. In August of the same year, pieces of meat dropped into a solution of borax and water (5 parts of the former to 100 of the latter) were there preserved unchanged for a month—being then taken out of the solution and exposed to the air, they dried slowly, and did not undergo decomposition. The next series of experiments was with a mixture of borax, sub-borate of ammonia, and tepid water, in the proportion of 5 or 6 parts of borax, and 10 or 12 of sub-borate of ammonia, to 100 of rain or pure river water. By injecting this mixture into the bodies of rabbits killed two days previously, the water kept them without sign of decomposition for several months. M. Jacquez is of opinion that this process is of high importance for the dissecting-room, as it does not alter either the coloring or the firmness of the tissues, and at the same time imports no poisonous element into the subject. Furthermore, the edge of cutting-instruments