for the Advancement of Science. 265 



thermometers— a subject to which the attention of M- Regnault and 

 Mr. Sheepshanks had been advantageously directed. And, with the 

 assistance of a portion of the sum placed by the Government at the 

 disposal of the Royal Society (to which I shall hereafter refer), it is 

 hoped by the officers of the Association that the Kew Observatory will 

 be made really efficient for the testing of new instruments. Dr. Rob- 

 inson s very instructive account of his new anemometer has latefy been 

 received: ihis instrument, however, has not yet been used in many 

 * places. Among the immediate deductions from magnetic observations, 



I may specially mention Col. Sabine's remarks on the periodical laws 

 discoverable in disturbances apparently of the most irregular kind, and 

 M. Kamtz's corrections of the Gaussian constants. 



Among the more distant results, there is nothing comparable to the 

 experiments into the magnetic properties of oxygen, and especially into 

 the variation of its power, made by Faraday and Becquerel, — and the 

 application of these results to the explanation of the phenomena, ia 

 almost all their varied forms, of so-called terrestrial magnetism. It is 

 to the former of these philosophers that this great step in the explana- 

 tion of obscure natural phenomena by inference from delicate experi- 

 ^ ments, is mainly or entirely due. Much, of course, remains to be 



V ^one, before we can pronounce accurately how far this principle ena- 



*^!es us to account, without any reference to any other cause, for the 

 regular changes, as well as for the capricious disturbances, in ordinary 

 l^agnetism. I ought not to omh stating that such general explanation 

 had long ago been suggested in a very remarkable paper by Mr. Christie ; 

 but the experiments actually applying to the magnetic properties of 

 oxygen were unknown, and perhaps impossible, at that time. In the 

 science of abstract magnetism, the distinction between paramagnetic 

 9nd diamagnetic substances has been thoroughly worked out by Mr. 

 Faraday, and is now received as one of the most remarkable laws of 

 nature. In the related subject of Galvanism, although much of detailed 

 ^aw has been established by the labors of the same great man and of 

 others, it is difficult to fix upon any new law of general character. 

 ■Gxperiments made in America seem to establish that the velocity of the 

 4 galvanic current in iron wires of a certain size does not exceed fifteen 



or eighteen thousand miles per second: a much greater speed, how- 

 ever, is inferred by M. Fizeau, from the same experiments. The first 

 part of an elaborate mathematical theory of Magnetism, by Prof. Thom- 

 son, has been published. 



In Meteorology, some striking facts have been collected and arranged 

 oy Col. Sykes in regard to India, by Messrs. Schlagenlweit in regard to 

 JJe Alps, and by M. Plantamour in the comparison of observations at 

 [geneva and the Great St. Bernard ; and some very unexpected facts 

 have been extracted by M. Arago from the observations on a balloon 

 ascent at Paris, The systematic collection of observations of luminous 

 Rieteors, in Reports by Prof, Powell, printed in the volumes of the 

 Association for the last two years, can scarcely fail to lead to some dis- 

 <:pvery of the origin and nature of those mysterious bodies. An exten- 

 sive series of meteorological observations bad been made at the Ord- 

 nance Survey Office at Mountjoy, near Dublin, and the Association 

 , ^'^'^® years since recommended to the government the early printmg 



Secoxd Seeies, Vol XII, No. 35.— Sept., 1861. 84 



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