1865.] Chemistry. 459 



an alcohol, and not as an acid. The compounds which this body 

 forms with alkalies are of a very indefinite character. It may be 

 distilled without loss from an alkaline solution, and although it 

 absorbs ammonia with avidity, it parts with it again when heat is 

 applied. When, however, the ammoniacal compound or mixture is 

 heated under pressure, aniline and water are formed. The so-called 

 acid and the hydrate here spoken of both dissolved oxide of lead, 

 and seem to form a definite compound C 12 H 6 2 + 2 P b O. 



A paper, by Mr. Church, on some Cornish minerals, communicated 

 the same evening, will be found noticed in its proper place. 



A note by Mr. C. L. Bloxam, on the action of Chlorine upon 

 arsenious acid made known the curious fact that in the reaction of 

 these two bodies at a moderate heat, one portion of the arsenious 

 acid, becomes oxidized at the expense of another, and thus terchloride 

 of arsenic and arsenic acid are formed. The latter combines with 

 arsenious acid to form a transparent glass, having the composition 

 2 As.0 2 , As.0 5 . 



At another meeting Mr. Bloxam read a paper " On the action of 

 Hydrosulphate of Ammonia on freshly-precipitated Sulphide of 

 Copper," by which it seems that a double compound of sulphide of 

 copper and sulphide of ammonium is formed. It is a very unstable 

 salt, which by great care can be obtained in vermilion-red crystals, 

 very like those of chromic acid. 



At the same meeting the same gentleman read some interesting and 

 valuable notes on qualitative analysis. The first related to the reduc- 

 tion of binoxide of tin by cyanide of potassium. Sulphate of potash is 

 often found as an impurity in commercial cynanide of potassium, and 

 when binoxide of tin is fused with such a mixture sulphides of potas- 

 sium and tin are produced, which combine together and dissolve when 

 the fused mass is treated with water, thus causing a considerable loss 

 of tin. In somecases both stannic and stannous sulphides are formed, 

 and when commercial cyanide is an anaylsis both of these should be 

 looked for ; the latter will be left as a black powder when the fused 

 mass is dissolved in water, and the former will be separated from the 

 solution on the addition of hydrochloric acid. 



Another note related to the detection of Zinc. Mr. Bloxam recom- 

 mends that the supposed sulphide of zinc precipitate should be dis- 

 solved off the filter with hot dilute nitric acid, and the solution mixed 

 with a very minute quantity of nitrate of cobalt. The whole should 

 then be precipitated with carbonate of soda, the product collected in 

 a filter, washed, dried, and afterwards incinerated on platinum foil, by 

 which the green compound confirmatory of the presence of zinc is 

 obtained. If the green colour should not be apparent at first, it will 

 become visible when the residue is moistened and crushed. In this 

 way the Professor said that 10 iooth part of zinc in solution might 

 be identified. 



"When testing for magnesia in the filtrate, from the ammonia and 

 sulphide of ammonium precipitates with phosphate of soda, a flocculent 

 precipitate sometimes makes its appearance at once, and obscures 

 the magnesian reaction. This precipitate Professor Bloxam has 



