gS Mr. Davy’s Lecture on some new analytical Researches 
white fumes which had a strong smell differing a little from 
that of muriatic acid. 
It reddened litmus paper in its common state, but had no 
effect upon litmus paper which had been well dried, and which 
was immediately dipped into it. It was a non-conductor of 
electricity. It heated when mixed with water, and evolved 
muriatic acid gas. I consider it as a compound of phosphorous 
acid, and muriatic acid, both free from water.* 
Having failed in obtaining uncombined muriatic acid in this 
way, I performed a similar process with sulphur, but I was 
unable to cause it to inflame in oxymuriatic acid gas. When 
it was heated in it, it produced an orange coloured liquid, and 
yellow fumes passed into the neck of the retort, which con- 
densed into a greenish yellow fluid. By repeatedly passing 
oxymuriatic acid through this fluid, and distilling it several 
times in the gas, I rendered it of a bright olive colour, and 
in this case it seemed to be a compound of dry sulphuric, and 
muriatic acid, holding in solution a very little sulphur. When 
it was heated in contact with sulphur, it rapidly dissolved it, 
and then became of a bright red colour, and when saturated 
with sulphur, of a pale golden colour.-f- No permanent aeri- 
form fluid was evolved in any of these operations, and no 
muriatic gas appeared, unless moisture was introduced. 
As there seemed little chance of procuring uncombined 
• I attempted to obtain dry muriatic acid likewise from the p’nosphuretted muria- 
tic acid ofM.M.GAY Lussac and THENARD,by distilling it in retorts containing 
cxygene gas, and oxymuriatic acid gas. In the first case, the retort was shattered by 
the combustion of the phosphorus, with a violent explosion. In the second, com- 
pounds, similar to those described above, were formed. 
f All these substances seem to be of the same nature as the singular compound, the 
lulphuretted muriatic acid, discovered by Dr. Thomson, noticed in page 9^. 
