480 Intelligence and Miscellaneous Articled. 



The two salts, in combining, obey then some other law than that 

 of their reciprocal affinity : this new influence M. Schaeuffele de- 

 scribes as the effect of masses. 



In fact, it cannot be mistaken that the relative mass of the con- 

 stituent salts has a peculiar action on the definitive product, since 

 it is always the sulphate that has served to form the saturated solu- 

 tion which predominates in the double salt obtained, and it is also 

 that which impresses its form on the product obtained. 



A fact, which had long escaped the notice of chemists, is thus 

 generalized, and to which M. Gerhardt first drew attention. What 

 happens in the preceding experiments may be assimilated to that 

 which is produced in the reaction of two solutions, according as one 

 is poured into the other. — Journ. de Pharm. et de Chim., Avril 1850. 



ON AllSENIC IN THE ZINCS OF COMMERCE. 



M. Schaeuffele observes, that it is not requisite to insist on the 

 importance of this subject. As zinc is not only employed in manu- 

 factories for culinary purposes and in medico-legal investigations, it 

 has become necessary to determine the relative proportions of arsenic 

 which it may contain. The experiments of the author were made 

 on four specimens of zinc of well-known origin ; and he submitted 

 them to the test of two methods generally applied in researches for 

 arsenic, those of Villain and Jacquelain. The former consists 

 in passing the arseniuretted hydrogen gas through a glass tube 

 heated to redness, and in weighing the metallic arsenic resulting from 

 its decomposition ; the process of the latter consists in passing the 

 gas through tubes with bulbs filled with solution of chloride of gold, 

 which it decomposes, giving rise to metallic gold, hydrochloric and 

 arsenious acids. 



M. Villain's method gave the following results, as the quantity of 

 arsenic contained in a kilogramme of each of the kinds : — 



gr- 



Zinc of France 0004260 



Zinc of Silesia 0-000970 



Zinc of Vieille Montague 0-000620 



Zinc of Corphalie 0000038 



M. Schaeuffele also examined ten other commercial samples of 

 zinc, hut of unknown origin ; and he found the quantities of arsenic 

 comprised between the above-stated limits. 



It results, therefore, from these experiments, that the zinc from 

 the mine of Corphalie is the purest of those met with in commerce ; 

 the author indeed admits, that, on account of the small quantity of 

 arsenic which it contains, it may be employed in medico-legal re- 

 searches without previous purification, which cannot be done with 

 the zinc of France without danger, it being the most arsenical of all. 

 — Journ. de Pharm. et de Chim., Avril 1850. 



