Nipher—Gravitation and Electrical Action. 171 
in the temperature of the room. It was found that the 
flame of a wax candle, placed fourteen inches from either 
of the suspended masses, exerted a marked apparent at- 
traction for them. When a sheet of glass and two sheets 
of asbestos paper were placed between the candle flame — 
and the metal shield, it being provided with a wrapping 
of asbestos paper in addition to the inside lining of the 
same material, an apparent attraction resulted. A change 
of 20 seale divisions would then result in two minutes. 
This result was obtained with either of the suspended 
masses, when the other was protected by the two 50-lb. 
masses and other means before mentioned. Fluctuations 
in the flame of the candle due to the condition of the wick 
produced observable effects. When the outer wall of the 
Screen was rising in temperature more rapidly on one 
side of the suspended mass than on the opposite side, this 
mass moved towards the warmer side. This was appar- 
ently due to the convection effect of air within the lining 
of the metal screen. 
The suspended rod bearing the small masses was below 
the central axis of the enclosing shield. If one side of 
the shield was warmer than the opposite side the sus- 
pended rod would be in a slowly drifting current of air, 
which would urge it towards the warmer side of the 
Screen, or away from the colder side. The temperature 
of the large masses lagged behind that of the screen in 
the small daily changes in the temperature of the room. 
The effect of a noiseless discharge from the pin-point 
terminal into the air around the knob connected with the 
Screen and the large masses, was to produce an apparent 
decrease in the attraction of the large masses for the 
Suspended masses. This result was obtained when no 
trace of disruptive discharge could be detected. After 
the extreme displacement thus produced had _ been 
Teached, the distance between the pin-point terminal, and 
the knob connected with the shield and the large masses, 
Was increased from 15 to about 90 em., the charged bod- 
tes being then grounded. This was done by means of a 
