4 BE ORBITA SOLIS 



CAPUT I. 

 Theorema 7. 



Fig. I 3. Sit datui radius circuli~?', et quadriUne- 



um ABDE a diametro AB et chorda parallella BEfgr- 

 matum-, aijus area Jit—zbb-, Erit hnc pa&o norinalis 



FC— ^^ I ^^ H ' ^'° -4-. _'-.3.&J^ , i.?!.i;.^'* 



2.3.r* a.-l-.ir' 2.4-.6.7.r^ 2. 4. 6. 8. 9. r''' 



Ponatur FCmx , et inde FE=|/(n-— .r.v)-, fit 



fe ipfi FE quam proxima , ut habeatur YfEe ele- 



mentum fpatii FCBE , kiVicet —Virr—xx ) dxj 



cujus integrale eft —rx—^ 



t x i . 3 .X 



2.3.r 2. 4-.? r 2.4.6.7.7- 



—^Z'. Extra<?la igitur radice ex hac lequa- 



tione, prodit .v— ^H — ^ 1— ^- h Q.E.D. 



2.3r* 2.4--'i/ 



Problema L 



FiS» 2« 4- £.v rt'^?^i-*' quatuor folis infun orhita locis , quo- 



, rum bma fibi oppoftta funt , et temporibus, quibus ibi 

 fol extitit , invenire locum apogiCi et eccentricitatem. 



Sit ALPM eccentricus orbita: ellipticse, in quo 

 quatuor data loca, V^^ij et <^i^,, quafi legitimc ad 

 eum reduda eflent , exiftant ( reducentur autem 

 poflmodum fi opus eft. ) 



QuO" 



