PHYSICAL CHARACTERS OE MIXTURES OE ALCOHOL AND WATER. 605 
Table VIII. 
Water value of calorimeter employed 1*248 grm. 
Water value of thermometer employed 0*632 grm. 
Specific heat of glass of bulb 0*19. 
Quantities taken of 
Per cent, by 
weight of 
alcohol con- 
tained in the 
Weight of 
glass bulb 
immersed. 
Temperature of 
calorimeter at 
Loss in 
thirty 
seconds. 
Corrected 
rise. 
Units of heat 
evolved by 
5 grms. of 
the mixture. 
Alcohol. 
Water. 
mixture pro- 
duced. 
Beginning. 
End. 
grms. 
79*830 
grms. 
8-870 
90 
1-7529 
18-091 
20-265 
0-083 
2-257 
7*7025 
73-2300 
18-4075 
80 
1-6049 
17*365 
20-700 
0-034 
3-369 
12-4775 
81-1280 
34-7690 
70 
2-6649 
17*128 
21-763 
0-041 
4-676 
18-8200 
62-1660 
41-4440 
60 
3-6849 
17*309 
23-348 
0-241 
6-280 
27*2620 
46-1850 
46-1850 
50 
9-3634 
17*567 
24-815 
0-277 
7*525 
35-5850 
37*0070 
45-2308 
45 
7*1494 
17*420 
25-053 
0-277 
7*910 
38*8095 
36-6375 
54-956.2 
40 
4-0449 
17*420 
26-001 
0-419 
9*000 
44-8630 
29*2340 
68-2125 
30 
2-3544 
17*337 
26-227 
0-250 
9-140 
47*9800 
22-8025 
91-2100 
20 
1-5069 
16-106 
24-202 
0-177 
8-273 
43-9545 
11-2345 
101-1105 
10 
1-3419 
17*295 
22-286 
0-069 
5-060 
26-6850 
Section III. — Boiling-points. 
About 100 cub. centims. of the mixture whose boiling-point was to be estimated were 
placed in a flask of about 200 cub. centims. capacity, closed by a doubly perforated cork. 
In one of the perforations a thermometer was fixed in such a manner that its bulb 
was about \ inch above the surface of the liquid, whilst nearly the whole thread of mer- 
cury was surrounded by the vapour of the boiling liquid. 
The steady boiling of the mixture was ensured by the introduc- Pig. 2. 
tion of broken pieces of tobacco-pipes, previously ignited, into the 
flask. 
In the second perforation a tube of moderately large diameter 
was inserted, which passed down to just beneath the surface of the 
liquid, the upper end being connected with a Liebig’s condenser. 
In this tube a lateral opening is made, by means of a blowpipe- 
flame, just beneath the cork; and through the opening thus made 
the vapour from the flask passes into the condenser, whilst the con- 
densed liquid runs down the tube, and is discharged just below the 
surface of the boiling liquid, having been raised nearly to the 
boiling-point in its passage down the heated tube. In this manner the composition 
of the liquid in the flask can be kept constant for a sufficient length of time to allow 
a tolerably accurate estimation of the boiling-point to be made. 
It was found that the boiling-points of distilled water and absolute alcohol did not 
vary ^oq- of a degree, whether the vapour was allowed to escape freely into the atmo- 
sphere, or was condensed and made to run back into the flask. It is, however, necessary 
to have the glass tube and condenser of a diameter large enough to allow the condensed 
liquid to run down on one side while the vapour escapes on the other. If this pre- 
mdccclxix. 4 M 
