SOLIS CIRCA AXEM. aSx 



qnem rnic obferiuuioni conformcm , fiuc ccrta qua- 

 dam r.itionc auctuni aflumamus. 



Punctum porro C rcferct ccntrum difci , ct 

 qnilibct circuhis niaximus pcr C ductus in difco 

 pcr Inicam rcdiim centriim traiicicntem rcprcfcnta- 

 bitur ,• pcr hoc pundum C tranfibit quoquc circu- 

 lus maximus in fupci"ticic Solis cclipticam rcfcrcns , 

 ad qucm cr-;o quilibct alius circulus maximus pcr C 

 ductus acque crit inclinatus , atquc cius fpccics in 

 difco ad rcdam EF, edipticam rcpraefcntantem. 

 Ncmpc fi CUGH fucrit circulus maximus pcr lo- 

 cum maculac M tranficns , cius inclinatio ad pla- 

 num cclipticac acqualis crit angulo ECM in fig. i. 

 cxprcfTo. 



Nunc igitur quacritur in fupcrficie Solis arcus 

 CM (cu angulus COM. 



SIT r fcmidiamctcr Solis apparcns , iam ra- 

 tionc quapiam autflus , prout hypothcfin circa ma- 

 cularum diflantiam finxcrimus ; 



in difco autem Solis fiicrit diftantia maculac a cen- 

 tro (fig. I.) CM = r. ^ 



Nunc igitur in fig. 3. habcbimus angulos 



OTD = r et OTM = .r 



vndc erit OT : ODzz i : fin.ri^OT : OM 



At cfl O M : O T =: fin. .v : fm. T M N zz fin. r : i 



hincque nancifcimur fui. TMN"^j^ 



ex quo porro colligitur angulus COM::=TMN — r. 

 ■^ Tom.Xll.Nou.Comm. Nn EX 



