82Experiment No. 3. The purpose of this experiment was to demonstrate principles C and D in Pars. 30 and 31. A modified form of the evaporation calorimeter as shown in Figs. 5 and 6 was used.“ The air was first passed through two layers of moistened sponge, bringing it very close to true
Fig. 14 Aspiration Psychrometer.
adiabatic saturation. Its temperature was then taken alternately with a wet-bulb and a dry-bulb thermometer, and simultaneous readings were taken with thermometer No. 4, the error of which had been established. It was found very difficult to obtain consistent readings to the degree of accuracy desired, on account of the extreme lag of temperature in the calorimeter thus constructed. On this account it was found necessary to maintain the tempera-
