f 
L ! 5 8 ] 
tiplying the other ; the power in the fir ft wheel, being 
in a ratio of *■ to the weight to be raifed, and -f- to 
the fridlion in its pevets j and the power of the fe- 
cond wheel in a ratio of ± to the weight, and t to 
the fridlion in its pevets j which powers are the lame 
as in the wheel A, viz. 2 _° with refpedt to the weight, 
and with refpedt to the fridlion ; although the 
powers required to counterballance the weight on the 
axis, are equal in each ; yet it would require a power 
above 733 pound to overcome the rehftance from 
fridlion in this engine, which is nearly treble the 
power required to overcome the fridlion in the wheel 
A, on account of four pevets rubbing on a dead 
furface in one, and hut two pevets in the other. 
By reducing the fridlion in the pevets of this en- 
gine, in the fame manner as in the pevets of the 
wheel A, the power 733 pound, which is required 
meerly on account of fridlion, may be applied to 
raife an additional weight of 14,650 pound, without 
any diminution in point of time, or velocity, with 
refpedl to the weight to be raifed 5 which at firfl view 
may feem contrary to the general principle, that 
whatever power is gained mechanically over weight, 
is loft equally in point of time, and velocity ; and is 
fo in reality, with refpedt to pradtical mechanifm ; 
For the faving a power, otherwife, hitherto, found 
neceffary to overcome the refinance from fridlion, 
and applying it to the ufeful purpofe of railing a 
greater quantity of weight, in equal time, is, in ef- 
fedt, equal to an acquifition of fo much power. 
If thefe wheels are made with tolerable exadtnefs, 
and placed, as in the drawing, on a line oppofite to the 
point of preffure of the pevets they lupport, the 
preffure 
