SULPHURIC ACID FOR WATER. 391 
APPENDIX 
TO THE FOREGOING PAPER. 
I perceive, under the head Sulphuric Acid, in 
the last of the monthly parts of Dr. Ure’s “ Dic- 
tionary of Arts, Manufactures, and Mines,” 
which is just turned out from the press, that 
an experiment has been made by M. Clement- 
Desormes, expressly to ascertain the effect of an 
elevated temperature in causing the process of 
the formation of sulphuric acid to go on freely ; 
the result of which showed the beneficial applica- 
tion of the temperature of 100°, in promoting the 
active agency of the aqueous vapour upon the 
gases. It is highly gratifying to find that my 
anticipations, arrived at from theoretical reason- 
ing, are in such a satisfactory manner corrobo- 
rated by direct experiment. 
From the conclusion of this experiment of M. 
Clement-Desormes, Dr. Ure seems to recommend 
maintaining the temperature of sulphuric acid 
chambers at 100° :—this he would do by the ad- 
mission of a jet of steam; it being discharged 
