‘ 
; 
On the Power of Fluids to conduct Heat. 381 
TEMPERATURE 
Time. at top. at bottom. 
2h. 10min. 72°5 58°r 
— 20 70 59— 
— g0 67 58x 
— 40 65 58+ 
mae 63 58 
Bh eae 62 58 — 
— 15 61 571 
= 90 - 592 57 
a. 572 56 (Air 52°) 
tisha 53 53 Do. 
A similar result was obtained in a different 
way by the following. 
Experiment 3. 
Took an ale glass of a conical figure, 22 
inches in diameter and 3 inches deep; filled it 
with water that had been standing in the room, 
and consequently of the temperature of the air 
nearly—Put the bulb of a thermometer to the 
bottom of the glass, the scale being out of the 
water: Then, having marked the temperature, 
I put the red hot tip of a poker, half an inch deep 
into the water, holding it there steadily about 
half a minute ; and as soon as it was withdrawn, 
I dipt the bulb of a sensible thermometer into 
