{ i7i ) 
fiances, that perhaps have been overlook’d, and at lafl, 
by a new Experiment, endeavour to fhew, what has 
led into an Error fome of thole, who defend the new 
Opinion. 
If a Man with a certain Force can move a Weight 
of fifty Pounds, through a Space of four Feet, in a de- 
terminate time ; it is certain he raufl employ twice 
that Force to move one hundred Pounds Weight, 
through the lame Space in the lame time. But if he 
ules but the fame Force, he will move the one hundred 
Pounds Weight but two Feet in the fame time. For 
as the one hundred Pounds Weight contains two fifty 
Pound Weights, if each of them has two Degrees of 
Velocity given to it, it will exadlly require the lame 
Force that would give one of them four Degrees of Ve- 
locity ; hence it appears, that the Force is propor- 
tionable to the Mafs multiply ’d into the Velocity. 
EXPERIMENT L 
Fig. I. Let the Balance A B, whole Fulchrum, or 
Center of Motion, is at C, be fo divided, that the Bra- 
chium A C be but the fourth Part of the Brachtum 
CB ; it is known to all Mechanicians, that a Weight 
of one hundred Pounds at A, will keep in .^quiltbrio 
a Weight of twenty five Pounds hanging at B, where 
it will have a Velocity four times greater than that of 
the Weight at A. For, not only when the Balance is 
horizontal, there will be ^inAiquilibrium^ but when the 
Balance is put in Motion, it will return to JEquili- 
brium in an horizontal Pofition ; the equal and con- 
trary Forces applied at each, dellroying one ano- 
ther. Whereas, if the Forces were as the Mafs multi- 
ply’d into the Square of the Velocity, the twenty five 
Pound Weight fiiould have been fulpended at D, only 
U 2 twice 
