33 
Steam Engine. 
VIII. On the contrary^ vapours-, during their conver-^ 
Sion into a liquid forniy evolve, or give out, much caloric. 
The heat given out, by the condensation of steam, is ren- 
dered apparent by the following experiment : Mix iOO 
gallons of water at 50°, with 1 gallon of water at 212®. 
The temperature of the water will be raised about 
Condense by a common still-tub, 1 gallon of water, from 
the state of steam, by 100 gallons of water, at the tempe- 
rature of 50 0 . The water will be raised 11®. Hence, 
1 gallon of water, condensed from steam, raises the- tem- 
perature of 100 gallons of cold water more than 1 
gallon of boiling water ; and, by an easy calculation, it 
appears, that the caloric imparted to the 100 gallons of 
cold water by 8 pounds of steam, if it could be condensed 
in 1 gallon of water, would raise it to 950^. (Black’s 
Lectures, i. 169.) 
For exhibiting the same fact, by means of a small ap- 
paratus, which may be placed on a table, and with the as- 
sitance only of a lamp, the boiler already described (fig.^ 
46) will be found extremely well adapted. The right 
angle pipe e must be screwed, however, into its place, and 
must be made to terminate at the bottom of a jar, con- 
taining a knov/n quantity of water of a given temperature. 
This conducting pipe and the jar should be wrapped 
round with a few folds of flannel. Tlie apparatus being 
thus disposed, let the water in the boiler be heated by an 
Argand’s lamp, with double concentric wicks, till steam^ 
issues in considerable quantity through the cock c, which 
is then to be closed. The steanri will now pass througlt 
the right angled pipe into the water contained in the jar, 
which will condense the steam, and will have its tempera- 
ture very considerably raised. Ascertain the augmenta- 
tion of temperature and weight ; and the result will show'-, 
how much a given weight of water has had its tempcra- 
* I eamiotgive the figure here. T. C. 
Vo!, II. E 
