94- D£ SJTERFICIE CTLIKDRI , ET C0A7, SCJL. 



:=:j ; KM, ndius circuli =r ; DE, nltitiido cylindri 

 fcaleni z= a \ ME, huiis hiiius cylindri , — If \ MVziz 

 V(/f* — a^ — c. Atqiic tnnit , ob panillclas Bl tt MD, 

 nngiili MBP ct CAl]) ncqualcs ^ adcoqnc , ob rcftum 

 MCD,^§.3)critCDM— BMP— PKM. Ell autcm , 

 pofito finu toto —I , finus PKM~j,K~-,r^ vnde iii 

 triangulo rcdangulo MCD d.ibitur hacc analogia , fin. 

 ]\1 C D [i): M D ( i- ) = fin. C D Al ( i-) ; M C ( 7) ; crit igitur 

 E C — T ' ( .M E '- - M C ' ) — ^^-^^- -l Cum autcm cx na- 

 tura circuU fit M;;/r= \,^r*-.j, ^ '• erit elcmcntum iMwr E 

 - M ;;; .v E C =r -^^.X;;;'''' = ^S , pofita lupcrficic A M 

 EFzrS. 



f. 5. Qiiod crgo clcmcntum vt intcgrctur , dclcriba- 

 tiir cUipfis ADB, cuius lcmiaxis maior ACzi r, lc. 

 miaxis minor DCn^, CE — r , EF:n/ ; critquc cx 

 natura clhplcos r : -^ =r — j :;■ , vndc t — ^, ■ , 



et F/zz nv^T^iTTiT- ; aut^Z^xF/=: -^[7X^.^7- — dS, 

 (§.4.) fubdituto ncmpc t' pro b*—a*\ oritur crgo ac- 

 quatio finalis hacc b. V fziz dS \ cjuac intcgrata pracbct b x 

 DF — S ; quia autcm pofito arcu D F ir. , fit >' rr 9 , 

 ct confcqucntcr ctiam S — 0, hinc conlluuc in hac in 

 lcgrationc adiicicnda opus non c(t. 



^.6. Ilinc igitur cmcrgit fcqucns conftru(flio inucnicn • 

 dac fupcrficici cylindri (calcni , dcmtis bafibus circul.uibus, 

 quod liucusquc (cmpcr fiiit intclligcndum. Ex ccntro balcos 

 ^S- »• fupcrioris O propofiti cylindri (calcni dcmittatur pcrpcn- 

 diculari^ O Q. •" plaiium bados infcriorib \ punctum Q 

 ct ccntrum bafcos infcrioris K coniungatur ada QK , 

 quac coustjuc in dircclum prolongctur , doncc cylindn la- 



lus 



