LENZ, E. (HEINRICH FRIEDRICH EMIL.). - ESTABLISHING LENZ'S LAW.

Ueber die Bestimmung der Richtung der durch elektrodynamische Vertheilung erregten galvanischen Ströme.

(Leipzig, Johann Ambrosius Barth, 1834). Without wrappers as issued in "Annalen der Physik und Chemie. Hrsg.von Poggendorff", 1. Bd., No. 31. Pp. 481-496 (entire. No 31 offered), Lenz's paper: pp. 483-494. Clean and fine.

First appearance of the fundamental statement of Lenz's Law, which says that the direction of a current produces by electrodynamic induction is always such as to oppose by its electromagnetic action the flux change which gave rice to it. The memoir appeared at the same time in "Mémoires and Bulletin" of the St. Petersburg Academie of Sciences.

"Lenz's name survives in the history of physics as the result of his discovery of two fundamental physical laws - soon seen as special cases of the law of conservation of energy - and a great many empirical quantitative relationships of electromagnetic, electrothermal, and electrochem,ical phenomena...His application of Ohm's law and Gauss's method of least squares and his graphical representation of various laws have distinguished his work from the scientific papers of most of his contemporaries.
In November 1833, Lenz read his paper Ueber die Bestimmung der Richtung der durch elektrodynamische Vertheilung erregten galvanischen Ströme" before the St. Petersburg Academy. It established Lenz's Law, relating the phenomena of induction to those of the ponderomotive interaction of currents and magnets discovered by Oersted and Ampère. Lenz's Law states that the induced current is in such a direction as to oppose, by its electromagnetic action, the motion of the magnet or coil that produces the induction. F. Neumann's derivation of the mathematical expression for the electromotive force of induction (1846) and Helmholtz's proof of the law of conservation of energy (1847) were based on Lenz's Law. This law also includes the principle of invertibility of motor and generator, which lenz demonstrated on Pixii's magnetoelectric machine in 1838."(DSB VIII, p. 187-188).

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.: 43354