116 * On the Measure of 
fulera are fixed, and whose perpendicular 
arms are equal, but the length of the hori- 
zontal arm of F’,. twice the length of the cor- 
responding arm of E. If C descends through 
the space S, D will descend through an equal 
space in the same time; and by these equat 
forces in equal times, A will have acquired 
exactly twice the velocity of B. Now if 
these effects are to be measured by the products 
of the masses into their velocities, D produces 
twice the effect of C, although their forces are 
precisely equal. 
In this and the following cases, the mass of 
the lever, &c. is supposed to be indefinitely 
small, when compared with that of the ball 
which it moves. 
2. If we suppose two balls, m and n, (fig. 2.) 
whose masses are as 1 to 2, to be suspended as 
in the last case, and put in motion by the 
pressure of the atmosphere on the pistons 
P and Q acting upon mand n, by means of the 
levers GL and AB; A F being equal to BF,. 
but G H=2 HI, and the area of the cylinder 
E twice that of C ; supposing these cylinders 
and the fulcra F and H to be immoveable, 
and the.space under each pistonto bea vacuum. 
Then E and C will move through equal spaces 
in equal times, and m will acquire just twice: 
the velocity of n. 
