( ‘^5 > 
partes^ ^ harum fupcrando cohiiefionem corpora amittere po~ 
fuere. 
8. Now the Rule for finding the common Velocity 
of Non-hlaRic Bodies moving the fame way after the 
Collifion, is, to divide the Sum of the Qtiantities of 
Motion in the two Bodies, by the Sum of the Quan- 
tity ot^ Matter. 
9. Tis alfo granted, Motu dmhus corporihus commu- 
n 't corpora hcec in fe mutuo agere non pojfe. In Sedl. 215'. 
Supplement. Fhyf, ■' 
I o. Fendet ergo i^us a velocitate refpe^iva., qua ma- 
nente intenfitas impathonis eadem er'it.^ quomodocunque 
celeritates ahjolutce varient. 
II.. Al intenfitare hac pendet partium introceJJtOi qua 
ergo femper eadem erit ft duo corpora eadem velocttate 
rejpethva in fe mutuo incurrunt^ qmhufcunque velocitati- 
hus moveantur. 
12. Thefe Principles furnifli us with an Argument 
againff the new Opinion. For if it be true, then e- 
qual Caufes may have unequal Effeds,‘ and that in 
their own fenfe of an Effedt : The Proof fhall be ta- 
ken from Inffances of the Effeds of the Collifion of 
Non-Elaflic Bodies, whofe refpedhve Velocities fliall 
be always equal. . . 
13, LetfATand fB) ftand for two Non-Elaflic 
Bodies of. equal Quantities of Matter ; and let fB^ be 
at reft, while (A^ moves towards it' with 8 degrees of 
Velocity. 1 c • 5-q 
‘•r- 
I. Here the common Velocity after the Stroke' 
will be half the Velocity of before the Stroke, 
i.e, 4 degrees. Confequcnrly the force in thus 
communicated by the Stroke will be as its Square, 
or 16. 
B b 
1. Let 
