SULPHURIC ACID AND WATER. 293 
to adopt his conclusion. He appears, unfortu- 
nately, to have fallen into an error, in looking 
upon the rzse of temperature produced as indi- 
cating the comparative number of degrees of 
heat evolved, which would only in reality have 
been the case if all the resulting mixtures had 
had one and the same specific heat: since each 
different mixture has a different specific heat, the 
requisite calculations must be made. ‘The ques- 
tions requiring to be answered are, How much 
heat will a compound formed of 1 atom oil of 
vitriol and 1 atom water, absorb in having its 
temperature raised 184°? How much will one © 
formed of 1 atom oil of vitriol and 2 water, 
absorb in having its temperature raised 211°? 
How much will one formed of 1 atom oil of 
vitriol and 3 water, absorb in having its tem- 
perature raised 207°? And how much will one 
formed of 1 atom oil of vitriol and 4 water, 
absorb in having its temperature raised 189° ? 
We cannot do better in answering these ques- 
tions than use water as a standard, and determine 
how many degrees water would have its tem- 
perature raised by having as much heat imparted 
to it as would be required to raise the tempera- 
tures of the four compounds in question the 
number of degrees assigned to each: and, as the 
rise of temperature produced upon a body, by 
