4-76 Intelligence and Miscellaneous Articles. 



is added to the sulphate of copper, the same quantity of precipitate 

 is not obtained. 



It results from the above-stated experiments, that the quantities 

 of the triple salt vary according to the proportions of water, and 

 whether the sulphate of copper is added to the sulphate of potash, or 

 the reverse ; when the proportion of sulphate of potash is increased, 

 a larger quantity of the sulphate of copper is decomposed, but with- 

 out in any case obtaining bisulphate of potash and the triple salt 

 only. 



As the proportions of the triple salt thus formed are variable, it 

 is natural that the solutions which yield it should differ in composi- 

 tion ; some are found to contain much of the copper salt, whilst in 

 others the sulphate of potash is in excess. 



On subjecting these solutions to careful evaporation, crystals of a 



double salt, S Cu SK + 6H'^ O, are formed, which by two or three 

 successive concentrations separate completely. It is a curious phae- 

 nomenon to observe such very soluble salts produced so perfect by 

 simple crystallization. The mother- waters eventually resulting from 

 these crystallizations are merely bisulphate of potash. — Ann. de 

 Chim. et de Phys., Mars 1849. 



ON OCTOHEDRAL AND CUBIC ALUM. BY M. J. PERSOZ. 



It is well known, that when a solution of octohedral alum is satu- 

 rated with potash, or for a short time put in contact with trissulphate 

 of alumina, it cannot be heated to 140° F. without becoming turbid ; 

 and there are formed octohedral alum, soluble at all temperatures, 

 and trissulphate of alumina, which is precipitated. When the solu- 

 tion, however, instead of being subjected to so high a temperature, 

 is subjected to evaporation at a gentle heat, cubic alum is obtained, 

 which readily becomes octohedral alum by dissolving it in water 

 slightly acidified with sulphuric acid. It may then be evaporated 

 and redissolved at pleasure without undergoing any alteration. 

 Lastly, if a certain quantity of cubic alum be dissolved in water and 

 boiled, it yields basic sulphate of alumina insoluble in water ; and 

 the mother-water and that used in washing, when mixed and evapo- 

 rated, give only octohedral alum. Hence it is concluded that these 

 two alums are not identical, and that cubic alum contains most 

 alumina. — Ann. de Chim. et de Phys., Mars 1849. 



ON ANISOL AND ITS DERIVATIVES. BY M. A. CAHOURS. 



Anisol presenting with respect to toluol (benzoene of M. Deville) 

 the same relations of composition that phenol does to benzene, the 

 author resumed the examination of this product, in order to complete 

 his researches respecting the compounds of the anisic series. 



It has been shown that anisol treated with fuming nitric acid ex- 

 changed 2 or 3 equivalents of hydrogen for 2 or 3 equivalents of 

 hypoazotic vapour. There was therefore wanting in this series of 

 the derivatives of anisol, its first term, that is to say, that which 

 would result from the replacement of 1 equivalent of hydrogen by 



