* 7 8 Miscellanies. 



such an odor of bromine as to be insupportable. The muscle of 

 putrid fish produces a still worse smell, and the same thing took place 

 with other marine products, as shell fish, sponges, &,c. — Quarterly 

 Journal of Science. 



5. Impure salt in France. — An account has lately been given 

 to the Academy of medicine, of certain impurities in common salt. 



- 



The salt used in Fere-Champenoise and the neighborhood havin_ 

 induced violent cholic, accompanied with swelling of the face, in 

 many of the inhabitants, M. Cosmenie has examined it, and found in it 

 bromine, bromide of sodium, iodine, and iodide of potassium. Sev- 

 eral of the members had been charged with the examination of the 

 salt used in Paris. M. Baruel had met with some containing iodine. 

 M. Chevallier had examined many specimens of salt that had been 

 seized, but had not found iodine in any of them. Some of them 



had been adulterated by the admixture of sulphate of soda.— Bulle- 

 tin Universelle. 



C. Theory of Voltaic Electricity, by Prof. Pfaft, of Kiel. 



In a letter to Gay-Lussac, of 15th July, 1829. 



Prof, de La Rive, of Geneva, having in an able memoir (which 

 was republished in the Ann. de Chim. of Nov. 1828) furnished some 

 striking results to prove the incorrectness of the fundamental thesis 

 of the theory of Volta relative to his pile, viz. that of the production 

 of electricity by simple contact, and to demonstrate that m all cases 

 it is chemical action, which determines this production— Prof. Pfaff still 

 holding to the theory of Volta, that contact alone generates the elec- 

 trical excitement, opposes the results of Prof, de La Rive, with rea- 

 sonings and experiments which appear at least very plausible. 



Prof, de La Rive maintains that the humidity of the hand, which 

 holds or touches the metal, and the oxygen and moisture of the air in 

 contact with the plates, are circumstances essentially concerned in 

 the electromotive power, and which are of course referable to chem- 

 ical action. Prof. PfafF objects to the correctness of some of the ex- 

 periments relative to the effect of more or less moisture of the hands, 



and observes that his results are opposed to those of Professor de La 

 Rive. 



But to prove that oxygen and moisture are by no means necessary 

 to electrical excitement in the contact of different metals, he formed 

 a condenser of a plate of copper and a plate of zinc, substituting i" 



