A simplified sketch of the conservation of energy, by American physics cartoonist Paul Hewitt (Ѻ), showing the transformation of chemical energy into kinetic energy into potential energy into the heat and the work of explosion of impact. |
“Kirchhoff’s predecessors in the field of radiation bore him much the same relation as, in the conservation of energy, Mayer, Colding, and Seguin bore to Joule and Thomson.”
“Besides the fifty-four known chemical elements there is in the physical world one agent only, and this is called Kraft. It may appear, according to circumstances, as motion, chemical affinity, cohesion, electricity, light and magnetism; and from any one of these forms it can be transformed into any of the others.”
“Force itself can never be destroyed.”
“The quantity of force which can be brought into action in the whole of nature is unchangeable, and can neither be increased nor diminished.”
“In any system of bodies whatever, to which no energy is communicated by external bodies, and which parts with no energy to external bodies, the sum of the various potential and kinetic energies remains forever unaltered.”
“Energy can be neither created nor destroyed.”
“Nothing can be lost in nature—no energy can be destroyed.”