igitur fuperefl, vt ctiam videamus, au ifli valorcs cum nume- 

 ratorc ipfius y conueniant, quo rcquiritur, vt fit b c — adzn i ; 

 eft vero bc — — cnf.[g 1 ct atf=fin.£g 1 vnde fit bc — adzz — i. 

 Probe nutem notnndum cft , nmbas coordinatas tnm pofitiue 

 qunm negntiue funji pofle , itn vt liic perfefta identitas agnofci 

 debent. 



§. 20. His vnloribus inucntis mnnifcflum efl, formulas 



noftrns gencrnles perducluras fuiflc nd hanc proiectionem fte- 



reographicam , fi pro funclione A :s aflumfiflemus ftatim hnnc 



formnm ; 



fin. \ g - z cof. \ g tang. \g - z 



fiue 



cof. I g + z fin. fg j ■+• z tang. ; g ' 



Cctcrum hic obferuari conucnict , iftum cafum ad vfus practi- 

 cos, quos in Geographia poflulamus maxime efle accommoda- 

 tum, quandoquidem vernm figurnm rcgionum terreflrium non 

 admodum detorquet. Imprimis nutem notnri merctur, quod 

 in hnc proie&ione non folum omncs Meridinni ct Paralleli 

 circulis vel ndco lincis rectis cxhibcnntur, fed etinm omnes cir- 

 culi maximi in Sphaera dcfcripti etiam per arcus circularcs vcl 

 adco lincas rcc"tas exprimantur , dum e contrario aliac Hypo- 

 thefes, quae pro functione A fingi poflent, his commodis pe- 

 nitus eflent cnriturae. 



DE 



