A26 Scientific Intelligence. 
twenty cells of which were employed on this night. To give an idea 
of the force of this electro-magnet, Prof. Faraday mentioned that once, 
while he was at work in the laboratory, an iron candlestick which hap- 
pened to be standing on the table near its poles, instantly flew to them, 
attracted with such violence as to displace or break every thing in its 
way. The great experiment of the evening was then successfully 
tried. “A. prism of heavy glass was so adjusted between the poles of 
the magnet, as to receive the oxy-hydrogen light after it had been po- 
larized, and before it was depolarized by Nicholl’s eye-piece. The 
following facts, demonstrating the magnetism of light, were then ex- 
hibited: 
1. As to the rotation of the ray.—A polarized ray, having been ex- 
tinguished by the depolarizing plate, was instantaneously restored when 
the magnetic current was sent through the prism through which the ray 
was transmitted: and conversely, the polarized ray, when, by the com- 
mon adjustments of the plate, it had been made visible, was extinguished 
by the force of the current. 
2, As to the relations of this electro-magnetic power to other laws 
of polarized light.—The rotation having been established, it was shown, 
(a.) That the direction of the rotation was absolutely dependent on that 
of the magnetic force. (.) That, while in common circular polariza- 
tion, the ray of light always rotates in the same direction with regard 
to the observer, (to whatever part of the medium his view may be di- 
rected,) it is very different in the state of the ray induced by this new 
force. When brought under the influence of the magnetic current, po- 
larized rays always rotate in a constant direction with respect, not to 
the observer, but to the plane of the magnetic curves. 
Prof. Faraday concludes, by throwing out some general notions as to 
the possible development of these researches in the line of future in- 
vestigations. It did not seem impossible to him, that the sun’s rays 
might be found to originate the magnetic force of the earth, and the 
air and water of our planet might be proved to be the diamagnetic me- 
dia in which this condition of the force was eliminated. 
M. Pouillet has repeated the experiments of Faraday, and communi- 
cated a report to the Academy of Sciences of Paris, (L’Institut, No. 
630.) He is of the opinion that the phenomena are due to action on 
the transparent medium, or upon the forces which govern its molecules, 
and not on the luminous ray itself. 
3. Sound from vibration of soft iron, produced by a galvanic current, 
(L'lnstitut, No. 634, Feb. 1846, p. 65.)—This singular phenomenon, 
discovered by Mr. Page, and verified by M. Marrian, has been studied 
since by de la Rive and Matteucci. ‘These authors haye attributed the 
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