L 220 ] 
XIV. 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 appli- 
cation 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 1 i , 1815. 
! he Royal Society did me the honour of printing in the 
volume of their Transactions for last year, a paper of mine 
on the nature of the salts termed triple prussiates, and on 
acids formed by the union of certain bodies with the elements 
of the prussic acid. 
In that paper, I endeavoured to prove, that the elements 
of the prussic acid would combine with a certain proportion 
of black oxide of iron, and form a peculiar, and hitherto un- 
known acid, for which I proposed the name of the ferruretted 
chyazic acid. I showed that this was the real acid portion of 
the salts which had received the erroneous appellation of 
triple prussiates, and that the property of combining with the 
prussic acid, so as to change its nature, and increase its acid 
properties, was not confined to the black oxide of iron, but 
was possessed probably by many other bodies, but certainly by 
sulphur, which formed with it another acid, for which I pro- 
posed the name of the sulphuretted chyazic acid. The paper 
also contained some analytical researches into the proportions 
