234 DE TELESCOPtlS 



De Telescopils quinque lentibus 

 inflru6tis. 



16. Sccimda lcnte B antc focnm obitdiuae 

 conftituta , crit pro ea B — ^^^ et $5——^, rcli- 

 quae lentes fint dispofitae vt aiite idcoque C=r 7:3^ ; 



Q:=:c; DnFEpa; ©:=-«'; E=:~ et (£=i. Hinc 

 adperturas in coniputum duccndo ponatur brcuitatis 

 ergo n^=:-^0^-Cp; H" zzc 5'' -{- ^' - (^ ; U^'^ 

 — -_^0"''^-i-0'^-+-0' — Cp ac dcniquc u''''z=i^'''^ 

 _j_$/''/_^0^^_)_0'' — , dcnotante (p fcmiJiainctrum 

 campi conlpicui : ac fi multiplicatio flatuatur — w/ ^ 



crit Cp— ^^-^— ^^riTT'''"-^^ ) ^'^^'^ P^'^*-''^ ^^ fingulis 

 littcris O^, 0'''', 0^'''' ct ^"'^^ \alorcs ncgatiuos tribi;c- 

 rc liccret cosquc maximos , campum apparentcm 

 vltcrius augeri poflc. Sunt autcm bne littcrac d 

 eiusmodi fradioncs , \t (i p fncrit d ftantia foci 

 lcntis, ad quam rcfcrtur, ^p fit fcmidiamctcr apcrtu- 

 rae , vnde patet valores harum littcrarum non vl- 

 tra ^ augeri polfe. 



17. His pofitis habemiTS in generc pro lcn- 

 tium fmgularum dilluitiis foci earumquc intcrualHs- 

 (cqucntcs formulas , dcnotante a diftantiam foci len- 

 tis obicdiuac : 



;.. ^-P,. bc=-^;f^« 



-BCDg:p -.^T- _BcnD(n'^n^) 



* ac 



