Intelligence and Miscellaneous Articles, 159 



I hope to be able, in a few months, to comniunicate the results 

 of my fresh investigations on the physical and chemical properties 

 of davynm. The new metal appears to be a rare element in nature ; 

 platiniferous sand does not contain more than 0*04:5 of davyum, — 

 Comptes Rcndus de VAcademie des Sciences^ July 9, 1877, tome 

 IxxxY. p. 72. 



ON THE DIAMAGNETISM OF CONDENSED HYDROGEN. 

 BY R. BLONDLOT. 



Palladium charged with hydrogen acquires, as is known, the 

 properties of a true alloy. After Graham had discovered this 

 singular body, to which he gave the name of hydrogenium-palladium, 

 he endeavoured to determine its physical constants. His examina- 

 tion extended to its magnetic properties ; but there observation 

 seemed to falsify completely the previsions of the illustrious chemist. 

 In fact, it is known that palladium is feebly magnetic, while 

 gaseous hydrogen was classed by E. Becquerel and Faraday among 

 diamagnetic bodies ; therefore, in palladium charged with hydrogen, 

 one might have expected to meet with magnetic properties less 

 marked than in palladium not charged. "What happened was the 

 opposite of this. Graham ascertained that a piece of palladium is 

 attracted by the pole of a magnet much more powerfully after being 

 impregnated with hydrogen by electrolysis * ; and thence be 

 concluded that hydrogenium-palladium is more magnetic than 

 palladium. 



G. Wiedemann, in reporting in* his treatise on galvanism and 

 electromagnetism t the preceding experiments, refuses to admit the 

 conclusions drawn from them, attributing the phenomen'on observed 

 to the impurity of Graham's palladium, which " must have con- 

 tained oxide of iron ; the reduction of that oxide by the hydrogen 

 exalted its magnetic properties — which accounts for the anomalies 

 observed." 



In view of this disagreement it seemed to us expedient to submit 

 the question afresh to the test of experiment. The method we 

 employed is that which was devised by M. Becquerel for the deter- 

 mination of specific magnetisms. The body for experiment, in the 

 form of a small bar or strip, is suspended between the poles of the 

 electromagnet by a torsion-thread so as to make a determinate angle 

 with the line of the poles ; the current is caused to pass ; the bar 

 is deflected ; and to bring it back to its first position it is necessary 

 to twist the thread at its upper part a certain angle, which, after 

 suitable reductions, gives the measure of the specific magnetism 

 sought. 



* See Comptes JRendus, Jan. 18, 1869, p. 101 ; Phil. Mag. Feb. 1869, 

 [4] vol. xxxvii. pp. 128, 129. 

 t Die Lehre von Gnhanismus und ^lect7'omapietismt(s, vol. ii. p. 553. 



