HENRY, JOSEPH - THE DISCOVERY OF SELF-INDUCTION.

On the Influence of a Spiral Conductor in increasing the Intensity of Electricity from a Galvanic Arrangement of a Single Pair, &c.

(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. 540-547.

Henry's milestone paper announcing his discovery of electrical self-induction.
"Henry independently discovered electro-magnetic induction and in this paper announced his discovery of electric self-induction, one of the prime properies of an electro-magnetic circuit. Henry was an eminent experimenter but was casual in publishing his findings with resulting lack of recognition of his contributions."(Bern Dibner).

Dibner "Heralds of Sciece", No.63.

It was also printed the same year in "Transactions of the American Philosophical Society, New Series, Vol. 5". The paper was later printed in "Philosophical Magazine", 1840.

"The direction of Henry’s thought became somewhat apparent in his 1835 paper (refers to the papers reading before the American Phil. Soc., febr. 6th, 1835) on the action of a spiral conductor in increasing the intensity of galvanic currents. The paper started out as an affirmation of Henry’s priority in the discovery of self-induction. He then combined induction proper (using Faraday’s findings and his own) with selfinduction to show how these produce a pattern of repulsions yielding an increased effect in spirals. He specifically linked these “magneto-electrical” results to the principles of static induction developed by Cavendish and Poisson. This explanation was then applied to Savary’s report of changes of polarity when magnetic needles were placed at varying distances from a wire in which a current was being transmitted ("Mémoire sur l’aimantation," in Annales de chimie et de physique, 34 [1827],. That is, currents appeared periodically in the air surrounding a current-bearing straight wire as a result of the actions of induction and self-induction." (DSB).

Wheeler Gift: 2724-2725a.

Order-nr.: 47418