Mr. Brett's Analysis of some Double Salts of Mercury, 235 



suffer the gaseous products to pass off in their moist state, 

 and in calculating the products of the analysis to allow for the 

 increase in volume by moisture. 



The results arising from my analysis of alcohol and aether 

 do not favour the view which is very generally taken in the 

 present day of the vinous fermentation and its products, to 

 prove the inaccuracy of which, it is only necessary to make 

 experiments and to examine them in all their parts with 

 ordinary attention. Indeed the erroneousness of the com- 

 monly received theory is evidenced by the combination of 

 carbonic acid gas with vinous liquors, with aether and water, 

 and with alcohol and water, when a compound very different 

 from sugar is the product. 



The true theory which appears to run through every part 

 of the composition and decomposition of vegetable matter can 

 only be obtained by continuous and extensive observation. 

 An outline of a part of the necessary course of experiment was 

 laid before the Royal Society about two years ago. It must 

 ever be borne in mind that the entire series of results presents 

 itself in one continued chain, each link holding its necessary 

 position and its just proportion. Isolated experiments, like 

 broken links, lose their value, and bewilder and mislead the 

 inquirer. 



Walworth Road, Jan. ] 3, 1838. 



XXXV. Analysis of some Double Salts of Mercury, By 

 R. H. Brett, Esq., F.L.S,, M.R.C.S., ^'c.^ 



T^HE combinations of iodide, bromide, and chloride of po- 

 -*- tassium with bicyanide of mercury were spoken of in a 

 former paper. The iodo-cyanide of potassium and mercury 

 had been described by Liebig and Dr. Apjohn ; the bromo- 

 cyanide of potassium, together with the combinations of the 

 bromides of the other alkaline and earthy metals and bicyanide 

 of mercury, by Caillot in the Journal de Pharmacie : the new 

 salt which I then described, and of which I was not able to 

 find any previous mention, was the chloro-cyanide of potassium 

 and mercury. All these salts possess the same crystalline form 

 and atomic constitution: they are therefore isomorphous. The 

 salts about to be described are also isomorphous with those al- 

 ready noticed, and atomically considered differ only from those 

 described by Caillot in the substitution of the elementary 

 atom chlorine for bromine ; they are double salts, in which one 



* Communicated by the Author. 



