PHYSICAL CHARACTERS OE MIXTURES OF ALCOHOL AND WATER. 
603 
b. Spirit 20 per cent. ; amount taken 33*6255 grms. 
Experiment. 
t". 
T. 
t. 
f. 
* 
e. 
| Specific heat. 
73. 
18-0 
75*60 
16*723 
18*549 
0*008 
1*834 
104*55 
74. 
17*3 
75*45 
16*500 
18*329 
0*008 
1*837 
104*59 
Mean specific heat 104*570. 
Relying on these experiments and the considerations above mentioned, the authors 
have no hesitation in saying that some undetected error must have vitiated the elaborate 
research of Schnidaritsch. 
Lastly, a few experiments have been made in which the copper weight, instead of 
being heated, was cooled to zero Centigrade, by enclosing it in a well-fitting metal box 
of very thin brass, the whole being placed in a vessel filled with small fragments of ice. 
In about two hours the lid of the box was taken off and the copper weight rapidly trans- 
ferred to the calorimeter, which had been previously filled with liquid. The lowering 
of temperature produced is inversely proportional to the specific heat of the liquid in 
the calorimeter. All evaporation which the introduction of a heated body could produce 
is thus entirely avoided. 
Weight of copper gilt ring 614*49 grms. 
Amount of liquid in calorimeter 859*3 cub. centims. 
Copper value of calorimeter and thermometer 58*70 grms. 
a. Distilled water. 
In three experiments the value of N was 15*450, 15*510, and 15*901. Mean 15*62. 
b. 20 'per cent, spirit. 
In three experiments the value of N was 16*549, 16*112, and 16*365. Mean 16*342. 
Specific heat of 20 per cent, spirit 104*62. 
The temperature of calorimeter at beginning was about 19° C. 
The weight produced a depression of about 1°T5 C. 
The results of these experiments do not agree among themselves as well as those ob- 
tained in previous experiments, chiefly from the temperature of the cooled weight not 
being ascertained, but being assumed to be zero Centigrade in each case. 
The following Table (Table VII.) gives the mean result of all the foregoing experi- 
ments, the theoretical specific heat of each mixture being given as calculated from 
the proportions of alcohol and water present in each mixture. 
