[ I 53 ] 
The weight of the power, or predure, of the at- 
mofphere taken at 14 pound per inch fquare, 
,22,274 pound, with the pillar of water 10,060 
v pound, and alfo of the leaver, See. 12,000 pound; 
amounting in the whole to about 22 tons, center in 
the axis of the leaver. The quantity of friction re- 
fulting from this weight, fuppofed equal to half, or 
1 1 tons, hanging on the pevets 6 inches diameter, 
the leaver being 27 feet long, requires a power at ei- 
ther end — 425 pound to overcome its refinance in 
the leaf! degree, and muft dill require a further 
power to overcome the fridion of the other parts of 
the engine, and give the leaver a degree of velocity 
= 120 feet per minute. 
Before I give an account of the method I took to 
reduce the quantity of fridion in the pevets, it may 
be proper to mention a general error in the manner 
of placing the axis of the leaver under the beam. 
A ballance, having its center of motion underneath, 
and equal weights at each end, being placed horizon- 
tally, will remain in that pofition ; as both weights 
are equidiftant from the center of gravity, which is 
perpendicular to the center of motion ; but when it 
is made to incline to either fide, it will continue to 
move on that fide, untill it becomes parallel to the 
horizon, with the center of motion above the bal- 
lance : for when either end is depreffed in the lead 
degree, as in fig. 3, it becomes more didant from 
the center of gravity; and the oppofite end which is 
raifed in proportion, is brought nearer to it, although 
both ends dill continue equididant from the center 
of motion. 
Y Fig. 
Vol. LIII. 
