194 



2 AS 



SO3 + -5 — h cw. When this body is put into contact with 

 *j 



water, sulphate of water is formed, and arseniuret of copper 

 deposited ; this arseniuret being hkewise at once precipi- 

 tated, when arseniuret of hydrogen is passed into a solution 

 of sulphate of copper. 



Dr. Kane found also, that when arseniuret of hydro- 

 gen is passed over chloride of copper, chloride of hydrogen 

 is set free, and the same arseniuret of copper is produced, 



2 AS 2 AS , , 



cLcu H — 5- H =z -^- CM 4. cl H. 



In examining the constitution of the alum, the analysis of 

 which by Dr. Apjohn, was read to the Academy last winter, 

 Dr. Kane found that the water had been estimated by that 

 chemist a little too high ; thus Dr. Apjohn gave 48,15, while 

 the true quantity amounts to 47,60. This small variation, 

 however, makes, according to Dr. Kane, an important dif- 

 ference in the theory of the body, as the number of equiva- 

 lents is reduced to 25 in place of 26 : and Dr. Kane looks 

 upon the salt as composed of — 



Sulphate of Manganese Mwo.sO3.Ho + 6 ho. 



Sulphate of Alumina a4 O3 -f- 3 SO3 + 18 ho. 



(mn o.ho) SO3 + (A/2 03 + 3 SO3) 4- 6 ho + 18 ho. 



In a temperature of 212° this salt loses 18 ho, and by 300*' 

 six of the remaining atoms. The twenty-fifth atom is retained 

 up to 600° : and Dr. Kane looks upon this salt as a remarkable 

 case of the replacement of amide of hydrogen by an oxide of 

 the same class ; he further stated that it was by this princi- 

 ple he was led to the repetition of Dr. Apjohn's analysis. 



Sir William Betham read a paper " on Etruscan Hand 

 Mirrors," particularly that figured in Dempster's posthumous 

 work De Etruria Regali, Vol. I. Tab. I, p. 78, from the ori- 

 ginal in the Cospian Museum at Bologna. 



