g 24 Report of the Committee 
cafe the ball was only three inches, and in the other 2 1 
inches, below the cover. 
The heat of the fleam therefore appears to be not 
fenfibly different in different parts of the fame pot ; nei- 
ther does there appear to be any fenllble difference in its 
heat, whether the water boil fall or flow ; whether there 
be a greater or lefs depth of water in the pot ; or whe- . 
ther there be a greater or lefs diftance between the fur- 
face of the water and the top of the pot; fo that the 
height of a thermometer tried in fleam, in veflels pro- 
perly clofed, feems to be fcarce fenfibly affected by the 
different manner of trying the experiment. 
Though, as was before faid, there was fcarce any dif- 
ference in the height of the quickfilver, whether the 
water boiled fafl or flow, yet, when the water boiled 
flow, the thermometer was a great while before it rofe to 
its proper height; and when it boiled very flow, it 
feemed doubtful whether it would have ever rifen to it, 
efpecially if the ball was raifed a great way above the 
furface of the water: but when, by making the water 
boil brifkly, the thermometer had once rifen to its proper 
height, the water might then be fuflfered to boil very 
gently, even for a great length of time, without the ther- 
mometer finking fenfibly lower ^ 
All 
(e) The reafon of this feems to be that, while any air is left in the pot, the 
fteam 
