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It was alfo perceptible, that the air was impelled 
fomewhat, tho’ not coniiderably, more forward by 
the addition of each hundred weight on the bel- 
lows : 
That the deeper the horizontal pipe was placed 
in the water, the lefs refiftance was made by the 
fleam : 
That in proportion as the heat of the fleam was 
increafed, by making the water boil more ftrongly, 
the refiftance to the prelfure of the air by the weight 
on the bellows became greater. 
It is a very doubtful matter, whether air forced 
thro’ boiling water would have anfwered the purpofe 
intended : but I believe it was never imagined, that 
air could not be readily forced thro’, until proved by 
the foregoing experiments. The attempt, tho’ it has 
failed demonftrably in that point, has produced the 
fame effedt from another caufe, as to faving coals, 
and throwing up more water. For, by the conftant 
care, that was taken during the time of making thefe 
experiments, to meafure the coals, to admit only a 
proper quantity of fuel to be laid on, and alfo to 
mark the time exadtly it took in burning ; the en- 
gine then did, and hill continues to require eight 
bufhels of coals lefs, in every 24 hours work, than 
it did before ; and alfo, from the regularity of its 
ftroke, to throw up more water ; the fame care be- 
ing required from the engineer, who can have no 
pretence for confuming more coals now, than ap- 
peared fufficient during the time the experiments 
were making. 
Tho’ fome of the properties of fleam are well 
known ; yet the degrees of expanfion it is capable 
of v 
