Page:Popular Science Monthly Volume 2.djvu/76

64 and flimsy, so that if it did catch fire no loss would ensue. The "plant of machinery" is of small cost in comparison with that used for making black gunpowder, and Schultze's wood-powder is sold at a price commensurate with its cheap production. An explosive is often "better known than liked," such as gun-cotton; but Schultze's wood-powder requires only "to be known to be liked," as a trial of it, lately made for the satisfaction of its readers by the conductors of the Land and Water journal, recently showed. Indeed, it was proved to give more penetration than gunpowder, and it costs less. There is also no smoke, and consequently the second barrel can always be used at once, instead of waiting for the smoke to clear away, as when using black powder.—Belgravia.

 

HE first task of physiology was to localize the functions of life in the various organs of the body which serve as their instruments. Thus digestion was assigned to the stomach, circulation to the heart, respiration to the lungs; thus, too, the seat of intelligence and thought was placed in the brain. Still, with regard to the latter organ, a reservation was thought proper, excluding the idea that the metaphysical expression of the intellectual and moral powers was the manifestation, simply and merely, of the cerebral function. Descartes, who is to be classed among the promoters of modern physiology, because he thoroughly understood that the explanation of vital phenomena must depend on the general laws of physics and of mechanism, expressed himself very plainly on this matter. Adopting Galen's ideas on the formation of "animal spirits" in the brain, he assigns them the task of distribution by means of the nerves throughout the animated machine, so as to carry to each of the parts the impulse needed for its special activity. Yet, above and apart from this physiological function of the brain, Descartes admits the soul, which gives man the faculty of thinking: it was supposed to have its seat in the pineal gland, and to direct those "animal spirits" which issue from and are subject to it.

Descartes' opinions as to the function of the brain would not bear the slightest examination by modern physiology; his explanations, founded on imperfect anatomical knowledge, produced nothing but hypotheses marked by the coarsest mechanical conceptions. Yet they