-*{ ) 79 ( £?§"• 



§. 10. Ex his igitur manifeflum e^: pro tiing. \(y-\-y') 

 eruendo, fequentem adhibendam effe conftruftionem. Oc- 

 currat recla AC circulo in pu&is P, Q, tumque ex P 

 ducantur ad B, D, rectie P B , PD quae circulum in 

 S,0 fecant, et per haec puncta ducantur reftae DS, BO 

 circulo denuo in punctis R, N occurrentes , denique iun- 

 gantur CR, CN, PR, PN. Porro producatur BD vs- 

 que dum re&ae P Q in T occurrat, et ex punctis A, T 

 ad R ducantur rectae AR, TR, circulum denuo in V 

 et N' fecantes. Deinceps bifcecentur arcus VN 1 , VN 

 in pundis Z et U et demiffis in diametrum P Q pergen- 

 dicularibus 2 Y, U L, ecit tang.i (/ +y) - }^\. 



§. ii. Tnuento autem angulo y-\-y k , finguli y, y l % 

 facile inuenientur, quum fit 



tang. \y tang. \y' — tang. jj. tang. <x\ 

 hinc enim fiet: 



cotly cof4/-f fin.i/ fi n « l.y' "• cof. \y cof. \ y 1 - fin. \ y fin. ly 1 



— cof jjicof. it -t-fin.jxfin. 7r:cof.p.cof.?r— fi11.jm.fin.7r, 

 id eft 



cof. | (y-y 1 ) : cof. \ (y -*-/) =: cof. (p. - tf) : cof. [* + #): Tab. III. 

 quae analogia pro cof.i (j> — /) concinnam fuppeditat con- F '&* 3- 

 ftructionem. Iungantur punfta N, V in peripheria circuli 

 et producatur reda N V vsque dum diametro P Q in K 

 occurrat, deinde capto angulo C K L — 90 - * (y -f- y') y 

 occurrat refta KL circulo in punftis L , L 1 , dico fore 

 ;-KCL; j/' - K C L'. Tumque fi ifta puntfa L, V 

 eum pundo A iun^antur reftis A L, A L', quae circnlo 

 denuo in pundis M,M' occurrant, angult KCM, KCM' 



dabunt 



