25i 



DE TELESCOPIIS 



^^^^l-i±S^^s±L^ vt habaimiis e-]-^,-"-^--^ 

 at^uc 



^ — " , fp,, n—yj s-f-r (7— M) 



-M n-r— y-4-M """ r * = — « j-» 



q — cr- 



•vnJe fit ^ — M4-*^^^^l-I»— • At eft <r<<i ct ^<<i, 

 quare cum fit (/«— i)iVl-f-^— 3 4-r erit 



2 -^r — » 



fcu M: 



.r(j -4- : 



(2-t-r— »,ia 



. r — wc) - 



— ;;— Yt flt 



Statuatur brcuitatis gratia nzz: — j^, 



^zz(i-fH)M eritqiie 9 -f t-Mizi^H^It^^ et ^-r 



: -e r — »1 



_ g 



I -t- n t 

 cMa 



at^iue 



f 



O^/ ^" "i . 



r (2 — cr-M» 



p^^/- — . M OL ; 



P , _ c- ,_ 



v: M g 



+-r-+-M » 

 Ma 



■L> > q — c r — M 



CD — — ~— 



^^ j — c q — cr — M 



D^ c (' — v)Mg 



li . — C i —q 



c e- 



'^ ^ (i-c/<-i)' (j-.;^r+Ml» 



et r O— j__^_t.uH|::H- 



P — (,_;](e_,)- i-.i-t.rH.M j 



45. Quo clarius indolcm huius cafus pcrfpi- 

 ciamiis , primum obfcruo ad tubum contrahciidum 

 neccflc cffc , \t y— fr— M^M. Statuamus crgo 

 q — cr — M — kMi ac pro M introducflo valorc rc- 

 pcrimus f =:-^jr— , hincque M =: — mrrZTkT 



k(, 



.70 ItC) 



et q~{i'\-k)M-\-fr, ac q-r—M- — 



Ex his propofita multiplicatione tfi y fu nitoquc nu- 

 mero k ficut pro tubo contraliendo vidibitur , ad- 

 huc Uttcrac f ct v arbitrio uoltro rclimiuntur, qua- 



lUIIl 



