[ r 55 ] 
As the power E, in the wheel A, with refped to 
friction in the pevets f is in a ratio of the femidia- 
meter of the wheel A to the femidiameter of the pe- 
vetf it is evident, that, by enlarging the diameter of 
the wheel A, or reducing the diameter of the pevets 
the power over fridion will be increafed in pro- 
portion; but whatever power is gained by enlarging 
the diameter of the wheel A, will be loft equally 
in time, or velocity, with refped to the weight C to 
be railed; and altho there will be no lofs in time, or 
velocity, by reducing the diameter of the pevets f; 
yet tnis cannot be done beyond the proper degree of 
ftrength required to fuftain the weight C &c. 
. ^ alfo appears that the power E with refped to 
fridion in the pevets f is in a ratio of its velocity 
to the velocity of the pevet f rubbing on a dead fur- 
face, it follows, that if the velocity of the part rub- 
bing on a dead furface can be decreafcd, whilft the 
velocity of the power D continues in the fame ratio, 
with refped to the weight C to be raifed on the axis 
B; the power E over fridion, will be increafed in 
proportion, without any lofs in time or velocity, as to 
the weight C to be raifed ; which may be effeded in 
the following manner, and the quantity of fridion re- 
duced to any degree that may be required. 
Fig. 2. Let the pevets / of the wheel A, turn on the 
peripheries or the wheels G. G. 3 feet diameter, whole 
pevets g, g, are 1 inch diameter, and the whole fric- 
tion will be transferred from the pevets f to the 
pevets g, which will then be the only parts rubbing on 
a dead furface, by which means the velocity of the 
power in the wheel A, to the velocity of the pevets g y 
will be in a ratio of 1 *„ 6 °. For as the pevets 4 
Vol. LI1I. X . inches 
