( ATA) 
lower specific gravity. The choice fell on enamel grains with some 
silver (tetrahaedra) and experiments made with these gave very 
satisfactory results. With a constant pressure, the boiling point of 
water remained constant to 0.002°; introduction of more enamel 
grains had no influence on the boiling point. Secondly, it had to 
be ascertained in how far the indication of the thermometer depended 
on the height of the column of liquid above the bulb. Experiments 
showed that a displacement of the thermometer of 1 cm. causes a 
difference of 0.010—0.030° in its indications. On adding water in 
such quantity as to increase the depth above the bulb by 1 cm. a 
change of temperature was noticed which was always larger than 
that caused by a 1 em. displacement of the thermometer, but the 
change of temperature was always smaller than 0.030°. This pheno- 
menon may be explained by the fact that in the latter experiment 
the mercury bulb remains in the same liquid layer, whilst in the 
first experiment it was transferred to a layer of a different “mixing”’. 
It is not a matter of astonishment that, even, when using these 
boiling vessels, a change in the position of the thermometer causes 
a change in its indication and about to the same extent as I noticed 
with glass vessels, if we consider that the vessels have a diameter 
of 6 em. At a very small distance from the side, the influence 
READINGS OF THE THERMOMETERS. 
Left Thermometer. | Right Thermometer. 
ANNEN SEE EE ee eee 
1.610 | 2.100 
1.598 1 em. higher 2.100 
1.610 # # lower 2.099 
1.598 » # higher 2.100 
1.578 2 » , 2.100 
1.553 3 »# ” | 2.099 
1.550 4 w a | 2.100 
1550 40 ter 7 | 2.100 
1.550 4 w ” 2.099 
1.552 3 # y 2.099 
labs x 7 2.099 
1.598 r 7 2.099 
1600 <a w 2.099 
