21 



The saturated solution of the new gas in water, when mixed with 

 alkaline solutions, does not immediately lose its colour, or neutralize 

 the alkalies, but after a time the hyperoxymuriates are formed, and 

 the colour disappears. 



In consequence of the doubt which now occurs concerning the true 

 nature of euchlorine, the author declines giving a name to the pre- 

 sent compound, till he can have an opportunity of making some new 

 experiments on that subject. 



Farther analytical Experiments relative to the Constitution of the 

 prussic, of the ferruretted chyazic, and of the sulphuretted chyazic 

 Acids, and to that of their Salts ; together with the Application of 

 the Atomic Theory to the Analyses of those Bodies. By Robert 

 Porrett, jun. Esq. Communicated by W. H. Wollaston, M.D. 

 Sec. R.S. Read May 11, 1815. [Phil. Trans. 1815, p. 220.] 



In a former paper the author endeavoured to show that prussic acid 

 would combine with black oxide of iron, or with sulphur, and form 

 with them peculiar acids, to which he gave the names of ferruretted 

 and sulphuretted chyazic acids ; and he examined in what proportion 

 the elements of these new acids are combined, as well as the propor- 

 tions in which the acids unite to different saline bases. 



Mr. Porrett's present object is to add the results of two new ana- 

 lyses, made with great care, and to correct those inaccuracies of ex- 

 periment, which are at all times unavoidable, by the assistance of 

 the theory of Dalton respecting the relative weights of atoms, and of 

 Berzelius respecting multiple doses of oxygen. 



The first compound here examined, is prussiate of mercury. Ten 

 grains of this salt were decomposed by hydrosulphuret of soda, and 

 yielded 9'3 of black sulphuret of mercury. The residual liquor being 

 treated with sulphate of copper, yielded 9' 7 of sulphuretted chyazate 

 of copper, which by former analyses is known to contain l - 38 prus- 

 sic acid. 



In order to determine the quantity of red oxide of mercury indi- 

 cated by the weight of black sulphuret obtained, 25 grains of cor- 

 rosive sublimate were decomposed by hydrosulphuret of potash, and 

 yielded 21 '5 grains; and since the quantity of red oxide contained 

 in the sublimate is known to be 79f per cent., it is inferred that 9 '3 

 black sulphuret are equivalent to 8' 62 red oxide ; and hence that 100 

 grains of prussiate of mercury consist of 13' 8 prussic acid, and 86 2 

 red oxide of mercury. 



For the purpose of determining the constitution of prussic acid, 

 Mr. Porrett effected its decomposition by mixing prussiate of mer- 

 cury with red oxide of mercury, in such proportion, that by the as- 

 sistance of heat, the whole of the prussic acid might be converted 

 into carbonic acid, azote, and water. By a number of trials he found 

 that this was not completely effected till the quantity of red oxide 

 added amounted to five times the quantity contained in the prussiate. 

 In the decomposition of prussiate of mercury alone by heat, it is only 



