154 ANNUAL OF SCIENTIFIC DISCOVERY. 



MAGNETIC FORCE OF OXYGEN". 



M. Becquerel, succeeding Faraday, has also established the fact that oxygen 

 is magnetic, and that atmospheric air, in virtue of the oxygen it contains, par- 

 takes of the same property. The mode of experiment to measure the force 

 exercised by a magnet on a gas in comparison with the effect produced upon 

 a body taken as unity, consisted in placing successively small bars of glass, 

 wax, etc., in a vacuum and in different gases, in order to determine the mag- 

 netic power of the gas by the difference of effect produced under these two 

 conditions. He thus established that the relation between the attraction of 

 oxygen by a magnet, and the repulsion in an equal volume of water, is pro- 

 portioned to the density of the gas, and that it is represented by 0*18 at the 

 temperature of 12 Cent. If we reflect that the earth is surrounded by a mass 

 of air equivalent in weight to a stratum of mercury 76 centimetres in height, 

 we can understand that a similar mass submitted to the incessant variations 

 of temperature and pressure, ought to exercise an influence on some of the 

 phenomena dependent on terrestrial magnetism. In calculating what is the 

 real magnetic power of this fluid mass, we find that it is equivalent to an im- 

 mense shell of iron, of a thickness of y^th of a millimeter, covering the entire 

 surface of the globe. The results of Faraday, Becquerel, and Matteucci, at- 

 tained by different methods, all agree. M. Plucker having reached other 

 results by a process of his own a method by weight Becquerel has renewed 

 his researches, and confirms anew his previous results. 



DE. BELL OX THE SO-CABLED "SPIRITUAL PHENOMENA." 



"We extract from the July number of the American Journal of Insanity the 

 following extract of a paper read by Dr. Bell, of the McLane Hospital, Mass., 

 at the recent meeting of the Superintendents of Insane Hospitals, assembled 

 in Boston. A paper on a similar subject was presented by Dr. Bell at a 

 previous meeting of the Association, held in Washington, D. C., but this, by 

 request of several members, was not reported. They considered that the 

 whole subject was then too immature, and so much connected in the public 

 mind with the ridiculous, as to make it inexpedient that it should be more 

 than announced generally as among the topics discussed by the Association. 



Dr. Bell commenced by expressing his surprise in finding last year that at 

 so large a meeting of persons, whose lives were spent in investigating the 

 reciprocal influences of mind and body, scarcely a single member had given a 

 moment's attention to a topic directly in his path, which, whether regarded 

 as merely an epidemic mental delusion, or as a new psychological science, 

 was producing such momentous effects upon the world. It was now said to 

 number over two millions of believers, had an extended literature, a talented 

 periodical press in many forms, and had certainly taken fast hold on many 

 minds of soberness and power. He was well aware how easily it was turned 

 to ridicule, and that there were many who would bo ready to ask, when 

 they saw lu sp!1 il >i;tvctors serin-; [y di -I'-.s'ng tlv.' sp'ritunl phenomena, Quis 



