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trial to be as follows, •[nz. When tiie water run full 
bore, at the rate of a gallon in 1 7 feconds, the heat 
of the water was found, by a mercurial thermome- 
ter held in the ftream, at the lower end of the pipe, 
to be 80 degrees above the freezing point, i8o de- 
grees being the heat of boiling water. When, by 
means of a turn-cock, a gallon of water was two 
minutes in running, then the heat was 140. At 
which rate the 45- gallons would be an hour and 
half in running through the iron pipe ; at which 
rate ly gallons will run through in 50 minutes, with 
fo confiderable a degree of heatj and if it was an 
hour running, the heat would approach ftill nearer 
to a boiling heat, when firft put into the ftill, which 
would forward the diftillation, if wanted. 
17. I pumped the heated water up again into the 
upper veilel ; and thus continued to circulate the 
heating water, till its heat was 160 degrees in the 
upper vedel, viz. within 20 degrees, or one-ninth 
of boiling, the heat requifite for plentiful diftillation. 
I was in hopes tliat if the water in the upper veflel 
could have been brought to a due degree of heat, 
and a ilill-head' were fixed on it, with its cooling 
worm-tub, then water might have been diftilled in 
fhips, by having the iron worm-pipe fixed in the 
chimney of the cook-room : Hut 1 found, that when 
ithe heat of the water in the upper veflel was 1 60 de- 
grees, viz. within one-ninth of boiling ; then, in 
running through the iron worm-pipe again, it was 
fo over-heated as to expand in the p pe, into an ex- 
plolive vapour, which hindered the running of the 
water. However I thought it not improper to give 
an account of this attempt, notwithflanding it failed. 
Not 
