( 475 ) 
of the conductivity of the silver may be perceptible, but it is not 
astonishing that this influence is no longer noticeable at a distance of 3em. 
In using these vessels, I again noticed that the lower down the 
thermometers are placed in the liquid, the smaller becomes the differ- 
ence in temperature between the different liquid layers. In the fol- 
lowing table, the thermometer on the left is displaced each time 
1 em. whilst the position of the one on the right was left unchanged. 
It will be noticed from this table that, when the thermometer was 
raised by 3 c.m., the mercury reservoir was surrounded by vapour. 
It is plain, that, if we want to get different concentrations by adding 
salt to the water or to the solution, we must determine beforehand 
what will be the influence at that position of the thermometer, 
of a definite increase of the depth of liquid above its mercury 
reservoir, so as to be able to make a correction if necessary. If 
still more concentrated solutions are to be examined, it is desirable 
to avoid the correction by successively introducing into the appa- 
ratus equal quantities of solution and taking care not to alter the 
position of the thermometer. I next made the following experiment 
to compare the two BeckMANN thermometers. 
Distilled water was introduced into both boiling vessels and the 
boiling point read off, the pressure being kept constant by means 
of the manostat. The pressure was then changed to such an extent, 
that the thermometers fell about 0.5°. After some time the thermo- 
meters were again carefully read off. This experiment was repeated 
at different tensions. 
I herewith communicate some of. the results. 
nae ; 
eammometee 1 |tieceomeer IE |) ee ee 
Readings. 
1,457 1.195 9,962 
I 0.884 0.622 0.269 
2.658 2.076 0.582 
IL 2.058 1.474 | 0.584 
2.090 1.508 | 0.582 
Ul iid 1.030 | 0.584 
| 
1.610 2.100 | 0.490 
IV 1.255 1775 0.490 
etc, 
