ct in proicc^tinnc E I V — S , ct inucnigetiir rclatio intcr 

 S ct J, fiuc ex cognito anguio j- angulus ipfi in proicdlio- 

 nc refpondens S determincrur. Hunc in fincm ponatur 

 arcus vcrticalis A i' :zz v , atque cx triangulo fphacrico 

 A p v , in quo dnnrur arcus Ap~h, p v zi. g et angulus 

 Ap V ziz s dcducitur 



cof. v — cof. g . cof. h -\' fin. g fin. h cof /, 



qno inucnto habcbirur rc<fta 0«;, cum fit AOv~lv ct 

 O V — . 2 cof. l V \ vnde porro , ob O i' . O V — O A' dc- 



ducitur O V zz — - — . lam cum.fit ef~2gy erit chor- 

 cof. i v 



da huius arcus 2 fin. g, ideoque radius plani circulum mi- 



norem ^ i;/ abfcindentis — fin.^, vnde conclndimus fore 



arcum evzi:sf\n.g; in proie(itione vcro cft arcus EV 



rrrS.IE, quorum iam arcuum ev et EV elcmenta de- 



bcnt cQTe in ratione diflantiarum a pundo O. 



§. 14. Supra §. II. inuenimus effc 

 E F - a (tang. ^-^-« - tang. "-^). 



F.ft vcro 



, 1 fin.a Jin.b fin.(a — h) r,t\n 



tang. a - tang. h = ^^^^^ -^^, — -^j;:^.-^ » ''"e 



, _ 7 iftn.(a — 6) 



tang. a - tang. h — ,-sns-=r67qrToj7(lHh tT » 

 cxprefilo igitur pro diametro parallcli proicdi transforma» 

 lur i.i hanc: 



^ '^ * *^ — coj.g -f-coj.h * ■ 



qua in vfum vocata ad fcquentem pcrducimur analogiam 



d s fin. S : ~^^^^ = O V : V = I : - /, ~ ^ y 



cx 



