FARADAY, MICHAEL. - THE MAGNECRYSTALLIC EFFECT.

Experimental Researches in Electricity. - Twenty-sixth Series. § 32. Magnetic conducting power. i. Magnetic conduction. ii. Conducting polarity. iii. Magnecrystallic conduction. § 33. Atmospheric magnetism. i. General principles (+) Twenty-seventh Series. On Atmospheric Magnetism - continued. ii. Experimental inquiry into the laws of atmospheric magnetic action, and their application to particular cases. (Sections 2797-2968 a. 2969-3069). Received October 9, - Read November 28, 1850 and Received November 19, - Read November 28, 1850. 2 papers.

(London, Richard Taylor, 1851). 4to. No wrappers as extracted from "Philosophical Transactions" 1851 - Part I. Pp. 29-84, textillustr. and pp. 85-122, textillustr. Both papers clean and fine.

First appearance of a historical paper in physiscs in which Faraday on purely theoretical grounds predicts the magnecrystallic effect and experimentally proves this prediction to be correct.

Faraday was successfull in explaining the diagmagnetic phenomena with his lines of magnetics force, and he now applies his concept of "lines of force" to magnecrystallic bodies. "A magnecrystallicsubstance would then be one which in the crystallised state would conduct onwards, or permit the exrtion of the magnetic force with more facility in one direction than another; and that direction would be the magnecrystallic axis. hence, when in the magnetic field, the magnecrystallic axis would be urged into a position coincident with the magnetic axis, by a force correspondent to that difference, just as two different bodies were taken, when one with the greater conducting power displaces that which is weaker" The prediction was shown to be correct; a body like bismuth became less magnetc when its axis was parallel to the magnetic axis than when it is perpendicular to it.

From 1831 to 1852 Michael Faraday published his "Experimental Researches in Electricity" in The Philosophical Transactions of the Royal Society. These papers contain not only an impressive series of experimental discoveries, but also a collection of heterodox theoretical concepts on the nature of these phenomena expressed in terms of lines of forces and fields. He published 30 papers in all under this general title.They represents Faraday's most importent work, are classics in both chemistry and physics and are the experimental foundations for Maxwell's electro-magnetic theory of light, using Faraday's concepts of lines of force or tubes of magnetic and electrical forces. His many experiments on the effects of electricity and magnetism presented in these papers lead to the fundamental discoveries of 'induced electricity' (the Farday current), the electronic state of matter, the identity of electricity from different sources, equivalents in electro-chemical decomposition, electrostatic induction, hydro-electricity, diamagnetism, relation of gravity to electricity, atmospheric magnetism and many other.

"Among experimental philosophers Faraday holds by universal consent the foremost place. The memoirs in which his discoveries are enshrined will never ceaseto be read with admiration and delight; and future generations will preserve with an affection not less enduring the personal records and familiar letters, which recall the memory of his humble and unselfish spirit."(Edmund Whitta

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