qu? triangnli G A D. Ilabemus itaqiip qnatnor refl.is A. G, 

 AT, OI), TL, in quibu.s r(\ ()L:AL_ G LTl) : I) L'i'A 

 {§. <.). Qtujre cum fit GL:AL- fjnGK:finAK {§. (.), 

 GI:DI=rrinGF:finI)F (J. r..), & TJ):TA _ fin IU):'nnR A 

 (J. -. ), fcquifur fin (^. K: fin A K— finG F.fin li DifinDF. 

 finliA, quod erat Theorenia propofiium ($. 3.). 



J. 9. Iluic ThroremiHi Ptolrm.ieus aliud tanquam 

 Coroll.jrium finc drmonltralione fubiun^it , quod hic brcvi- 

 ter dcmonftraire iuvabiL 



Tlicnrcma. 

 /;/ Stfharrcip f\ipetfuic cinnlonnn mnTimorum arcuhus 

 ^'g io ut fnprn diicHf t]uiUuHun<)ue .V/i. .70, /;/•:, G/i, vft 

 fmAGifmylE -fmGI) fm liFifm DF.fm BK 



Dcinonnmtio. 

 Duai?; c Spharrdc ccrtro C r.idiis CA, CD, C R, 

 qiii chordi.s proion-.iiis GK, GF, KF. in ].Mnulis L I, T, 

 occurrant, tri.i h.icc [)unfla crunl in linra rid.i L I T. inter- 

 feflionc ncmpe f)Linorum circuli ADlJC, & tii.iii^nli r« fli- 

 linei GKF. Qn.itiior it.i(|uc habcnius rcHas L'I', L(i, 'I K, 

 CI, in (juibtis h.wc ol^linct ])ioporlio: LG : L K _ Ci L1'F: 

 IF.TK ($. .:.). Quirc cum fit {§. - ) LCi:LK-finAG: 

 finAK, IG.IF - finl)(i:finI)F, TF:TI<: finr.F:finl'K, 

 nanciscimur Cn A U:fin A E_:i finDG.fin liF:lin DF.finbE. 

 a K. D. 



f. To, Nihil i.Tm fupcrrft , nifi ut oftcnd.imus , qtio 

 paHo e dii[)Iici h(K; Thcnrcmatc omncs Tii;;ononi( liia( S[)hae- 

 ricae })rop.jrlione8 dcrivaii , oinniaque quae in tiian^nlis 



fpiuc- 



