§. 57. Vocauimirs aiitem arcivm 2 S rr ^ et ar- 

 cum Z ^ — •>!, aiquc pro data loci latitudine = Ct) ct Pa- 

 rallaxi — 71 inuenimus interuallum S 21 — 7t fin. ^. Hinc 

 ergo erit 



£) -— 4'I1-_1__ — A firt. <f 



/in. (ZS— ss) — /20, (^ — TTjm.iJ * 



At vero e(l proxime 



fin.f^-Trfin.^jzi^rin.^cof.fTrfin.O-Trcof.^nn,^, 

 idcoque 



/i!Lll=r yi"^) - cof (lt fin. <^) - TT COf. ^, 



et quia cof. t fin. (^ — i — 1 tt tt fin. ^% vbi quidem poftrc- 

 nuira membrum fatis tuto ncgligcre liceret , habebimus 



A 



I — -n Cof ^ — ^ TT TT fin. ^' ' 



Translato igitur denominatore in numcratorcm, ob 



,— -1— -— I 4-a-haa, quia hic azz Trcof^^-i-sTnrfin.^*, 



reperietur 



D — A ( I -h TT Cof <^ -!- ^ TT TT fiu. ^* -\~ TT Tt COf ^'), fiuC 

 D — A ( I -h TT COf < -f- „: TT Tt ( I -f- COf <^') ) , . 



quod poftremum membrum num poffit omitti finc errore 

 fenfibili videamus. Sumamus igitur ir — ^'j et <^ — o, fiet- 

 que i TT TT ( I -h cof (^' ) — ,c 51 » et cum A fit circiter 32', 

 eius pars 3600""' facit circiter femi-minutum fecundum , 

 vnde hoc mcmbrum tuto rciiccre licet. 



§. 58- Ex Diamctro igitur horizontaTi' A Diame- 

 ter apparens D erit D — A ( i -j- tt cof ^). Quoniam er- 

 go in detcrminatione Parallaxeos fupra vbique arcum 



M m 3 ■ . Z S 



