LENZ, E. (HEINRICH FRIEDRICH EMIL.) - ESTABLISHING ELECTROMAGNETIC LAWS.

On the Laws according to which the Magnet acts upon a Spiral when it is suddenly approached to or removed from it; and on the most advantageous mode of constructing Spirals for Magneto-electrical purposes.

(London, Richard and John E. Taylor, 1837) No wrappers. Extracted fron "Scientific Memoirs, selected from The Transactions of Foreign Academies of Science and Learned Societies. Edited by Richard Taylor.", Vol. I. Pp. 608-630.

First English edition of Lenz' first importent paper on electromagnetic induction.

"Lenz worked out the theoretical and practical aspects of the ballistic method of measuring electrical and magnetic quantities (1832) on the basis of his conception of the instantaneous, impactlike effect of induction current. Employing this method, he was able to make the first quantitative investigation of the induction phenomena themselves. (He established that the induced electromotive force in a coil is the sum of the electromotive force in each turn and does not depend upon the diameter of the turns, the thickness of the wire, or the metal of which it is made.) He also made a quantitative comparison of the resistivity of wire of different metals, established the laws of temperature dependence of resistivity in quadratic form for eight metals, derived the squarelaw variation of the attractive force of electromagnets with the magnetization current (under the conditions of the experiment, the magnetic field was proportional to the magnetic induction), and plotted curves showing the intensity distribution of magnetization along an iron core of a coil of finite length."(DSB).

Lenz was born on February 12, 1804 in Dorpat, and died in Rome on februray 10, 1865. He became professor of physics at the University of St. Petersburg. He investigated the conductivity of many materials for electricity and the effect of temperature on conductivity. he also studied the heat produced by the current and discovered the law which is known by the name of Joule.
(Magie "A Source Book of Physics" pp.511-13).

Order-nr.: 47413