O B I E C T I V 1 S. 391 



X rr 3, 1243» ideoque VX— 1 = 1, 4-575. 

 Qiiare tum ficri deberet 



„ ,. ^ . . Santerioris =r 1, 7302 11 

 Radius fliciei ^p^j^.rions =:o,34-3^n 



fin aiitem confufio toUenda O fuerit maxima- 2,1243 



ideoque X = i , iu prima lente erit 



„ , ^ . . Canterioris —0,324811 



Radius laciei •', n ■ • ^ n 



^poftenoris z=z 2, 374<5 n 



ficque tales lcntes triplicatae ad omnes confufioncs 

 toUendas a minima fcilicet O zr o, vtque i-naximam 

 0—2, 1243 erunt accommodatac. 



§. 22. Cum autem tanta confufio tollenda nun- 

 quam occurrat , in gratiam praxeos ftatuamus lentem 

 tertiam vtrinque aequaliter conuexam, ita vt liabeamus 



0,7555 + TVX''- 1 — i,i3C3-ry V— I hincqus 

 r y X" — I — o, 1869, 

 vnde concluditur X" — i, 040S , vnde fit 



3, 0540 X" =: 3, iSpo , 

 confequenter 



X — 2, 9993 — O. 

 Hoc autem calu pro tertia lcntc fict 



Radius vtriusque faciei — — ^- rr o, 3917 II 

 exidcnte lentis mediae 



radio vtriusque faciei rr — o, 3127 n j 

 Conftrudio autem lentis primae cx formulis paragr, 

 precedeatis eft pctenda > Iktim atquc valor ipfius X 



iuerit 



