Learned Societies. 36*9 



steel, it hi on the contrary the north pole which is the most 

 oxidahle, and the south pole the least. 



M. Ritter concludes his report with conjectures upon the 

 application of his results to the earth, considered as one 

 great magnet. In this he finds the explanation of several 

 phaenomena, chiefly of the physical diversity of the two he- 

 mispheres and of the aurorce borealis and australis. 



According to these principles, the earth considered as a 

 magnet may be represented as equivalent to a Voltaic column 

 of an enormous size, in which the poles are on one hand in 

 continual communication by the intermedium of the waters 

 of the ocean ; while on the other the superabundant electric 

 matter, finding no conductor, flies off into the free spaces of 

 the heavens, and there produces the polar aurora. 



LXII. Proceedings of Learned Societies. 



PHARMACEUTIC SOCIETY OF PARIS. 



_L he above society has announced two prizes, the one a 

 gold medal of 200 franks in value for the best essay, and 

 the other of 100 franks in value for the next in merit, ou 

 either of the nine following questions : 



1. Does there exist a process for constantly obtaining 

 kernics of the same colour and- nature ? 



What are the causes of the differences presented by 

 kermes, prepared several times successively after the verv 

 Bame process ? 



2. How comes it that whey does not always clarify of 

 the same colour ? Why does it sometimes redden, and 

 sometimes render green the blue colours? And to what cause 

 ought we to attribute its faculty of keeping a longer time 

 in vessels of tin than in those of clay ? 



3. Which is the best process for obtaining the purest an 1 

 most energetic emetic ? 



What change does the emetic tartar, or it? solution ih 

 pure water, undergo through time, either on account of the 

 action of light, air, or heat ? 



Vol. 25. No. ioo. Sept. 1806. Bb What 



