114 ANNUAL OF SCIENTIFIC DISCOVERY. 



employed consisted of a delicate balance, the beam of which was of 

 glass, and which gave a perceptible deflection of 0.0001 milligramme. 

 The gases examined were enclosed in spheres furnished with stop-cocks 

 and attached to one of the arms of the, balance ; these were capable of 

 resisting an internal pressure of about two atmospheres. The sphere 

 of glass, containing the gas, was placed over the two half armatures of 

 a powerful electro-magnet, and then the attraction or repulsion meas- 

 ured by means of weights placed in the opposite scale-pan. The 

 trifling'amount of magnetism in the glass was exactly compensated by 

 the magnetism of the surrounding air. The following were the prin- 

 cipal results obtained : 



1. The specific magnetism of oxygen, compared with that of iron, as 

 unity, was found to be 0.003500. 2. Oxygen loses its sensible mag- 

 netism in almost all gases where it enters into chemical combination. 

 Deutoxyd of nitrogen, NO 2 , is an exception to this rule, its mag- 

 netism being two fifths of that of oxygen. 3. If we introduce oxygen, 

 little by little, into a sphere containing NO 2 , the magnetism dimin- 

 ishes, till the proportion of the two gases is sufficient to form hypo- 

 nitric acid NO 4 , when the magnetic action becomes insensible. On 

 adding more oxygen, the magnetism reappears. 4. Hypo-nitric acid 

 NO 4 , when condensed into a liquid, is diamagnetic. 5. The magnetism 

 of oxygen, deutoxyd of nitrogen, and magnetic mixtures is propor- 

 tioned to the density of the gas. G. A magnetic gas, mechanically 

 mixed with any other indifferent gas, preserves its magnetism, what- 

 ever be the density of the mixture, only in the neighborhood of the 

 poles there appears to be, to a certain extent, a separation of the 

 gases, which must slightly augment the attraction of the entire mass. 

 7. A magnetic gas, which has been for some moments attracted by an 

 electro-magnet, is very readily repelled, if the polarity of the magnet 

 be changed. Hence, it appears that gases possess a very distinct 

 coercive force. Comptes Rendus, 33, 301. 



ON THE PROBABLE 11ELATION BETWEEN MAGNETISM AND THE CIRCULA- 

 TION OF THE ATMOSPHERE. 



LIEUT. MAURY, in a recent supplement to the Washington Astronom- 

 ical Observations, brings forward some arguments to show a probable 

 connection between the magnetism of atmospheric oxygen, and the cir- 

 culation of the atmosphere. Before the discovery of Faraday, that the 

 oxygen which composes one fifth of the atmosphere was magnetic, Lieut. 

 Maury, in the construction of his " Wind and Current Charts," had 

 conceived the existence of some agent, whose office, in the grand system 

 of atmospherical circulation, was neither understood nor recognized. 

 He found that the agencies of heat and the rotation of the earth would 

 not furnish a complete and satisfactory explanation of the distribution 

 of moisture and the circulation of the atmosphere over the earth's sur- 

 face. A new agent was required, and this, there is reason to suppose, 

 exists in the magnetic properties of oxygen. The facts adduced by Lieut. 

 Maury in support of this new view are as follows : From the zone of 

 calms, near the tropic of Cancer, which extends entirely across the 



