152 DE CALCVLO MOTVS 



bit;i fpccliint. Practcrca vero pro ipfius orbitiic va- 

 riatioiic , habcmiis : 



. I —aKudr-fir .. c fin. (0 — \p) , i i » 



_d u) — g B u dl-cof.a (i'i. ;9 — vl») , i j^ _ d vj» 



J;r. o) 1" U Cp Vtj' ijj') — taf.°. j- 



Ac dcniquc arguincntum latitudinis cr ad eadcm 

 clcmcnta rcuocatur opc luiius acquationis d(jizd<^ 

 — r/vlycof.cj. 



XXL 



Elcmcntum tcmporis dt cum quantitatc con- 

 ftantc cL coaimodinimc cx calculo tollctur , fi mo- 

 lus quidam rcgularis ct cognitus introducatur , \c- 

 luti motus medius folis , vcl alius corporis , quod 

 circa ccntrum virium in circulo vniformitcr rcuol- 

 vitur. Ponamus crgo circa corpus in A pofitum 

 cuius mafHi (it — ?l aliud corpus , cuius mafla — (£ 

 ad dillantiam ~a in circulo ita circumfcrri vt tcm- 

 porc t angulum ipfi proportionalem r ablbluat , 

 atquc nollrac formulac ad lumc cafum accomnKx^a- 

 bnntur llatucndo A — Si^CnClct Bno, ita -st 

 tum fiat •v—J-a ct d(p — dr. Motus igitur , qucm 

 cognitum aifuminuis, iiis duabus aequationibus con- 

 tinctur : 



>v*dp'-2aDdi" ctdv-{-vvd(P'-2adt\':i-\ Cf\;-j) 



tbi primum confiantcs D ct f luiic cafui conuc- 

 nientcr definiri oportct. Hunc in fincm cx priori 

 vrtlor 2art'/'~— p- in altcra fubllitutus dat : dv^ 



ll.U 



