[FOR THE USE OF MEMBERS. | 
opal Jrustitution of Great Brita. 
1851. 
WEEKLY EVENING MEETING, 
Friday, January 24. 
Sir R. I. Murcutison, Vice-President, in the Chair. 
Proressor FaraDAy 
On the Magnetic Characters and Relations of Oxygen and Nitrogen. 
In a Friday Evening discourse on the diamagnetic condition of 
flame and gases, delivered on the 14th April, 1848, Mr. Faraday 
called attention to the singular condition of oxygen gas in its rela- 
tion to the magnet. It was then demonstrated that this gas was 
magnetic by its carrying a cloud of muriate of ammonia (itself dia- 
magnetic) to the poles of the magnet, around which it seemed to 
gyrate in vortices. A more elaborate paper on the same subject had 
previously appeared in the Phil. Mag. for December, 1847. 
Last year M. Becquerel, not aware of these researches, had redis- 
covered the high magnetic character of oxygen, made some indepen- 
dent investigations, and derived numerical results from them. These 
inquiries Mr. Faraday does not consider to interfere with, but strongly 
to confirm his own. 
Oxygen is one of the most remarkable of known bodies: it forms 
one half of the aggregate of all matter. Important as are its mag- 
netic properties, it seems incapable of receiving permanent magnetism 
like steel or the natural loadstone.—By a series of elementary 
experiments the audience were led to discriminate between these 
bodies, and soft iron, nickel, cobalt; which unless while under an 
extraneous magnetic influence, have no attractive force. Oxygen 
being of the latter class, it is not certain that, even while it possesses 
an attractive power, it is in the exact condition of the permanently 
magnetical body from which it derives it. 
Were oxygen highly magnetic in the same extent as iron is, the 
immense quantity of magnetic power which would in that case be 
constantly undergoing variation by combustion, respiration, &c., 
would cause the most serious disturbances in nature. It is necessary 
to the conservation of the present state of things that the magnetic 
power in a given bulk of oxygen should be comparatively small. 
The audience were therefore told to expect no great demonstration 
of magnetism; but the extent to which that power does exist in 
oxygen and air, was proved by the following experiments : — 
No. 1, B 
