ON PYROACETIC SPIRIT. 
207 
not unite with or decompose it. But when hydrochloric acid 
gas is passed through this spirit, the gas is absorbed, heat is 
evolved, and the liquid becomes brown. Totally to change 
two ounces, it is necessary to continue to act upon the spirit 
for two days. The resulting dark, heavy liquid is to be 
washed with water, and then digested upon litharge, and 
afterwards upon fused chloride of calcium. This liquid is 
impure chloride of mesityl, and is dark colored and soon de- 
composes, becoming acid from the liberation of hydrochloric 
acid. Pure chloride of mesityl may be obtained by acting 
upon one volume of mesitic alcohol by two volumes of 
chloride of phosphorus, and adding, drop by drop, three or 
four volumes of water; effervescence ensues, which is to be 
moderated by the application of cold. A heavy, slightly 
colored fluid is obtained, which is to be washed with the 
smallest quantity of water possible, and then poured upon re- 
cently fused chloride of calcium, which separates the water 
and is not itself soluble in the chloride. Any attempt to pu- 
rify this liquid by distillation, decomposes it with the libera- 
tion of hydrochloric acid. The formula, C 6 H 5 C1, expresses 
the composition of this substance. 
Iodide of Mesityl — Hydriodate of Mesitylene. 
This is prepared by acting upon mesitic alcohol by iodine, 
phosphorus, and water, aided by heat. It is volatile, and dis- 
tils over; its probable composition, is C 4 H 5 I. 
When mesitic alcohol is acted upon by the oxygen acids, it 
becomes hot, and of a dark brown color. The acids combine 
with the mesitylene and form new acid compounds, capable, 
when neutralized, of forming salts with bases. With sulphuric 
acid, two acids are formed, varying in composition according 
as this acid is used in a greater or lesser proportion. To these 
acids the names sulpho-mesitylic,and persulpho-mesitylic acids 
are given. With lime, baryta, and lead, these acids form 
soluble salts. 
Persulpho-mesitylate of lime forms, upon evaporation, a 
deliquescent granular mass, which cannot be dried completely, 
