Page:Scientific Memoirs, Vol. 2 (1841).djvu/13

SCIENTIFIC MEMOIRS.

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VOL. II.—PART I.

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Article I.

Electro-Magnetic Experiments, forming a Sequel to the Memoir on the Application of Electro-Magnetism to the Movement of Machines; by M. H. Jacobi, Doctor of Science, and Professor at the University of Dorpat ^[1] . Second Series ^[2]

[From a Pamphlet kindly communicated by the Author.]

24.

The question relative to the magnetic power of hollow, soft iron tubes, magnetized by an electrical helix, occupies an important place among the numerous questions presented to us in relation to the employment of the mechanical force of electrodynamic magnets. A short time previous to my departure from Königsberg, I had made reparations to undertake a series of experiments on this subject. I was happy to find Professor Parrot engaged in these researches, the important results of which will be found published in No. 16 of the Bulletin de l'Académie. This distinguished philosopher had the kindness not only to communicate to me part of these results previous to their publication, but also, at my request, entrusted to me the tubes described in his memoir, in order that I myself might institute similar experiments. These experiments are the subject of the following paper, which 1 have the honour of presenting to the illustrious Academy, requesting that they will judge of them with indulgence.

1. Translated by Mr. William Francis.
2. The First Series, together with Memoirs by Prof. Botto, Dr. Schulthess and Prof. Henry, relative to this subject, are to be found at p. 503 of the First Volume.