ees 
ney 
— A ae ee ee 
446 
temperature in the neck was found to vary considerably when the condi- 
tions, such as the angle at which the flask is held, and the height of the 
heating flame, were changed. This difference between the sulphur and 
diphenylamine baths is probably not so much due to the higher temper- 
ature of the former as to the great viscosity of the sulphur condensing in 
the neck of the flask. 
The tube containing the silver oxide had been placed in the neck 
rather than in the body of the flask in order to avoid possible variations of 
temperature due to spattering of the superheated liquid. Upon experi- 
ment, however, this superheating proved to be small. The Reichsanstalt 
standard thermometer showed the temperature of the liquid to vary 
under varying conditions between 445° and 445.5°, the temperature in 
the body of the flask between 443.5° and 444.5°. Since the thermometer 
may have been in error by 1 or 2 degrees (it was calibrated at 397° and 
505°) we will use, as the temperature in the body of the flask, 445°, the 
accepted value for the boiling point of sulphur. 
Four new experiments were now made similar to those already de- 
scribed except that the tube B containing the oxide was now placed 
entirely in the body of the flask. The direct method with the manometer 
was used. ; 
For illustration I will give the details of the first of these experiments. 
The mereury column, moving rapidly at first, gradually came to rest. 
Its position was read on a scale attached to the capillary. Table IV 
gives the distances of this column from the end of the manometer at 
intervals of about five minutes. The experiment was begun at 10:25: 
TABLE IV. 
Time. Distance in mm. 
10.32 65.0 
10.35 53.9 
10.40 49.0 
10.45 45.9 
10.50 45.5 
10.55 45.2 
11.00 45.2 
11.05 45.2 
11.10 45.3 
11.15 45.2 
11.25 ’ 45.2 
The apparatus was now broken at C and the manometer calibrated ; 
0.842 grams of mercury was required to fill the whole manometer, 
0.00413 grams to fill the end of the capillary to the point (45.2 mm.) 
where the mercury came to rest. If we assume Boyle’s law to be correct 
the pressure is Seat or 204 atmospheres. 
The results df this experiment and those of others made under the same 
conditions are given in Table V. 
