ci ^ ^ — -T- ( £?LL _i- ^jkl. 1 — 2 r cot. c — ^r (^^"f-JLl 



, _r_ £coA^--£q/. a )» j. f - , >_ ( coj. 6 — cqf.o)« 



~Jm.c coj.atof.b ^"'- » ^" ~J/n.c coj.acoj.b • 



Verum de Tabiilis, quae huiusmodi Formulae fuperfl^untur, 

 tenendum efl:, quod non poffint efle fatis exa(flae, fiquidem ipfa 

 formula principalis quae fundamenti loco adhibita eft, non 

 nili valorera approximatum ipfms c' — c contineat. Et pa- 

 rum fane huiusmodi Tabulis proficietur, fi nouo et aeque 

 fere operofo labore corredio [cx Parallaxi oriunda inue- 

 ftiganda fit. 



§. 12. Si in Tfum vocctur formula : 

 ( cof c - cof. a cof. b ) {i^V* = cof c' - cof. a' cof b' , 



V ' Jin. ajin, b 



adhuc alia eius redudio fatis elegans notari meretur. 

 Ponamus primum per c' indigitari arcum /» C , ita vt fit 

 b' ~ b, fietque 



Cof. C. P^ + cof.b.!in.{..'-a) _ ^^^ ^, 

 fm. a ' Jm.a 



tumque 



cofr'-cof^=:2 fin.^(^-0fin.'(^'+^) = '-2^i^' - ^^y^^^ 



— -:- ^(cof^cof^«'-fl -cof^cof ■ a'-i-fl , 



fm. a ^ \ 1 1 



vnde 



(cof b cof. : [ai - o) - cof. c cof. \[ai-\-a)) 



c — c'z=z(ai — a) j: -p — , , I , — \ , 



^ '' hn.a{in.[[c' + c) 



in qua formula primum pro fin. '^[c' -\- c) adhibcri poteft 

 fm. c , tum vero inuento proxime c —■ c' , dabitur quoque 

 fin.'^{c' + c) fatis exade. Dcinde fimili formula ex da- 

 tis arcubus a', b, b' et c' quaeritur b c, vbi iam arcus b C 

 per c indigitari poteft, erit enim 



_ ,^ (cofflcof i(^'- ^) -cofrcof :(^'+^ )) 



._C-c-.[b-b) rm.^fin.i(7T0 



Verum 



