===== (i30 == 



reclum progredi , vnde ad qnodnis tempus eius fltum feu di- 

 fhntiam O G zzz v facillime aflignare licebit, hoc obferuato fuf- 

 ficiet binas tantum diftantias inter corpora noffe , quo paclo 

 tota inueftigatio ad pauciores quantitates variabiles reducetur. 

 Si enim ponamus diftantiam AB—p et diftantiam BCzzz^, 

 ita vt fi t y — x ___ p et z—y zzz^, erit z — x zzz p -f- q. De- 

 inde ob y zzz x -\-p et s zzz x H- _p -f- _* , tres aequationes pri- 

 mo inuentae has induent formas: 



T dlx f. 



dt 2 pp ' (p-hq ) z ' 



II ddx-^ddp _\_ . JC_. 



at* PP^qq' 

 T JJ_ ddx-4- d )p-+-ddq _ _____ _B_ . 



4t* (p-t-q ) 2 Tq' 



vnde fi prima a fecunda, tum vero fecunda a tertia fubtraha- 

 tur, impetrabuntur binae fequentes aequationes pro definiendis 

 ad quoduis tempus t binis nouis variabilibus p et q: 



C C • . 



T ddp (A + B) _, _ 



dt 2 pp q~q ( p-h-q ) a ' 



II d ^ q ZZZ — A ( B-f-C ) 



dt 2 p p (_•-+-_ ) 2 qq * 



§. ii. Quoniam primo inuenimus effe 



A x -f- B y -j- C z zzz a t -f- (3 ., 

 fi loco y et z valores fupra affignatos fubftitiiamus, habebimus 



(A-{-B-hC)x-h(B-hC)p-hCq — at-{-(3. 

 Per centrum autem grauitatis G reperta eft haec aequatio: 



(A-f-B-f-C)<z;zzzaJ-f-|3, 



vnde tres quantitates x, yctz definire poterimus,- erit fcilicet 



X ~ V (B-f-Oj>— Cq 



A + B + C ' 



hincque porro fiet 



y — ^ + _ 



A 



z ~ v _1_ a»-»-( a '- n)g _ 



A-t-B-t- C 



R 2 §. 12. 



y zzz <z;-f- A ^~ r<7 et 



A-r-B t-C 



