= (87)=== 



ffindantiir E D r= E F =: tang. i'', EG — tang. =,", etc. eriint- 

 qiic circiili cx centro p per D, F, G diidi raniHcli i", 2*, 

 ctc. a mcdio vtiinqiic diUantcs. Ponatiir iam fiii.X~[jL, pi*o 

 radio ^^ 1 •, ct qnaenitnr chorda 5 ,a, 10 [j., Cic. giaduam, 

 ad radiiim E /> — cot. A in fcala afTnmta pcrtincns, eaquc ab 

 E ad f, et fic porro vtrinqne abfcindatnr: atque arcu E^ in 

 5 vel 10 partes acqnalcs diiiifo, et per dinifionnm pnnda ad 

 p rciftis dnclis, crunt illae Mcridiani i" a fo inuicem diilan- 

 tes. Si rcgio proiicicnda Acquatori fit propinqna, radii E /> 

 majores fient, qnam vt eorum opc cx centro p circnli duci 

 commode qucant. Sumatnr tunc E p pro axc , E pro ahfcis- 

 farnm initio, ablcindantur E « ru; .v ct « c m v in rationc finus 

 verli ad finnm rcdum ficque tot puncla e determinentur , vt per 

 ea circnlus ¥. r e vel manu libcra vel morc vfitato mcch.anico 

 duci pofiit: pariterque in cctcris Parallclis crit proccdcndum. 



§. 5. Quodfi rcgio proiicicnda fit Zona Acquatorcm 

 inclndens, faciie patct, Connm abirc in Cylindrum Sphacram 

 tangentcm. Fit ncmpc hitus Coni E/) — co, fi X — o. Pro 

 ccrcris Parallelis ell radins /> D ~ , "^ '^ ^ —5 — 00, vnde Ae- 



' /.••1. A. coj. (J ' 



quator omncjque Paralleli proiiciuntnr in lineas reda<^, acquc 

 ac Mcridiani in rcdlas iis normales. Gradus latitudinis in ca- 

 dera proportione tangcntium \c fupra crelcuut. Fit euim D E 

 z:i tang. [3. 



§. 6. Inquiramus nimc, qnoinodo, qnac ad bonp.m re- 

 quiruntur proiecflioncm, pcr han.c obtincaiuur. Primo quidcrn 

 rcquifito, vt Mcridiani Panillclis fint normalcs, fatisfit. Ad 

 cctcra quod attinct, ducaiur mcridianiis p -t, priori p F proxi- 

 mns, vt et Parallclus ixv Parallclo Dd infinirc propinquus.! 'Kp- 

 pcllctur ED~.v, arcus D n — j. Rcpracrcntct D^ longitb- 

 du.cni y gniduum, crit curuatura arcus Doj: 7° fin.X, vcl in 



par- 



