The soul of man : an investigation of the facts of physiological and experimental psychology / by Paul Carus.

  • Carus, Paul, 1852-1919.
Date:
1891
Catalogue details

Licence: Public Domain Mark

Credit: The soul of man : an investigation of the facts of physiological and experimental psychology / by Paul Carus. Source: Wellcome Collection.

Provider: This material has been provided by King’s College London. The original may be consulted at King’s College London.

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    most prominent physiologists. But it received its death-blow, when the law of the conservation of en- ergy was recognized to the full extent of its importance. We now know that all forces in nature are motions of some kind : light and electricity are undulations of ether ; heat is a molecular vibration ; and mechanical motion, change of place or visible movement, can be transformed into any other energy, electricity, light, or heat. Vice versa, motion can be reproduced from the other energies. Energy* certainly often seems to disappear and can apparently be created again. But it can be shown that energy, when it disappears, reappears in another form, and that the energy thus created did exist before, it was only transformed. Energy may be latent ; and latent energy can be set free again. Because latent energy can be set free again, it is called potential en- ergy (Z. L. potent talis, from possum, I can). Suppose my hand exercises a force represented by A B upon your hand, and your hand resists the pres- sure by exercising an equal force in the opposite direc- tion B A, there will be no motion. Let the stress between the two hands represent the force of A B-\-B A. This stress is latent energy; it .is potential and can be converted into an energy of motion, or, as it is termed, into kinetic energy. If it takes a pressure oi A B to set the spring of a toy gun, the spring will exercise the same amount of force (B A) upon the catch that keeps it compressed. *L(jibiiitz called a force that acts as motion of some form vis viva, or '' liviiit; force. He defined vis viva as the product of the mass by the square of tlie velocity, M V . But now the term kinetic energy (from Kt.vi~v, to move), cnerKy of motion, lias become customary, and we understand by kinetic enert,'y h;ilf the mass times the square of velocity (i,^ M V'^). See Maxwell, Tlieory of J-feat, page go.