Note 7 — Chapter XIX · LATENT FORCE IN INTERSTITIAL SPACES—ELECTRO-MAGNETIC RADIATION—MOLECULAR DISSOCIATION.

It is always interesting to trace the germ of a scientific idea, hypothesis, or established truth. A writer in La Lumière Electrique, vol. xlv., has drawn attention to the fact that Descartes gave a theory of magnetism, in 1656, which resembles the modern conception of lines of stress in the ether. He considers that all magnets are traversed by a subtle fluid which flows out at the North Pole, and curving round, in the ether, re-enters at the South Pole, thus completing the circuit. Some of the greatest doctrines of science have recurred again and again, like the motif of a piece of music, until they finally assume a definite shape and become a working part of human progress; as will be seen when Keely’s system is recognized. ↑