This page needs to be proofread.
(867)
theory concerning the same Subject; imparted to the R. Society Decemb. 17, last, though entertain'd by the Author divers years ago, and verifi'd by many Experiments, made by Himself and that other excellent Mathematician M. Rook before the said Society, as is attested by many Worthy Members of that Illustrious Body.
Lex Naturæ de Collisione Corporum.
VElecitates Corparum propriæ & maxime Naturales sunt ad Corpora reciproce proportionales.
| Lex Naturæ |  |
Itaque Corpora R. S. habenia proprias Velocitates, etiam post Impulsum retient proprias. |
| Et Crorpora R. S. improprias Velocitates haebntia ex Impulsu restituuntur ad Æquilibirum; hoc est, Quantum R superat, & S deficit à propria Velocitate ante Impulsum, tantum ex Impulsu abstrahitur ab R & additur ipsi S & e contra. |
Quare Collisio Corporum proprias Velocitates habentium æquipollet Libræ escillanti super Centrum Gravitatis.
Et Collisio Corporum improprias Velocitates habentium æquipollet Libræ super bina Centra æqualiter huic inde à Centro Gravitatis distantia: Libræ verro Fugum, ubi opus est, producitur.
Itaque Corporum æqualium improprie moventium tres sunt casus. Corporum vero inæqualium impropriæ moventium (sive ad contrarias sive ad easdem parters) decem sunt omnino Casus, quorum quinque oriuntur ex Conversione.
| Inæqualia. | Æqualia. |
 |
 |
