C 95° ] 
quare B K = / D E = 'A x D E. Jam per 
§ , e ft CD = 4^x(I+^G + ^) 
etCE = r.i-r.C'U 
2 z J 
* G + b) * G + Tt)’ 
i B 1 
quarum fumma D E, dudta in — dat aberrationem 
quaefitam B K = iS^ x D E = 
O 
i — r. B 1 L 1 
2 i 1 
[fi+ir 
i (s + i x : ) + (r + i)’q7 + L Tr)]' < i ua! 
poft evolutionem terminorum fubtradta de L B, five 
B, relinquit diftantiam pundti concurfus L K 
B 
i — r. B 1 L* 
2 A 
L l . < ‘+3 r 2/ ' + 3 r , *4-0 
Aa z + A 1 a ' A 3 I 
. r » + 3 r i 2i + 3 r . * + r \ 
+ Bb l B 1 b ' B 3 J 
Porro quoniam pundtum C eft focus ipfi A con- 
jugatus rcfpedtu faciei primag, erit L C = = 
i A a 
r a 
i — r . A 
et quoniam idem pundtum C eft focus ipfi B conju- 
gates refpedtu fuperficiei fecundas, erit LC ~ 
iBb iAa 
per § 2. Hinc : 
r . B — r b 
iBb 
i — r . B — r b 
, adeoque B 
■ r . A — r a 
r A a b 
flve S + 5 
i — r . A , a -J- b — r a b 
_____ y j j 
— x — f- — . Dato fic valore iplius 
r a b r 
B, cognofcitur diftantia concurfus radii refradti G K 
cum axe five LK, ejufque aberratio a foco B five 
B K, quag ob fignum — fumenda eft a foco B contra 
diredtionem 
5 
