17316171[Figure 71]
dem proportionibus;
&
rectangulis in circulo A H B,
A T B, ſunt æqualia rectangula F H G, R T Y; ergo
vt rectangulum D E B, ad rectanguium D V B, ſic
rectangulum F H G, ſeù Q S Z, ad rectangulum
R T Y. Sed vt rectangulum Q S Z, ad rectangu-
lum R T Y, ſic armilla circularis Q S Z, ad armil-
lam circularem R T Y. Ergo vt armilla ad armil-
lam, ſic rectangulum D E B, ad rectangulum D V B.
Sed vt rectangulum D E B, in portione ad rect an-
gulum D V B, ſic rectangulum C D A, in parabo-
la ad rectangulum C F A; & vt rectangulum C D A,
ad rectangulum C F A, ſic D B, ſeù F H, ad F G,
ex ſchol. propoſit. 22. lib. prim. Ergo vt armilla cir-
cularis Q S Z, ad armillam circularem R T Y, ſic
H F, ad F G. Cum vero puncta V, F, ſumpta ſint
arbitrariè; ergo concludemus omnes armillas circu-
lares tubi parallelas armillæ N L P, eſſe ad omnes
armillas circulares exceſſus portionis ſupra
A T B, ſunt æqualia rectangula F H G, R T Y; ergo
vt rectangulum D E B, ad rectanguium D V B, ſic
rectangulum F H G, ſeù Q S Z, ad rectangulum
R T Y. Sed vt rectangulum Q S Z, ad rectangu-
lum R T Y, ſic armilla circularis Q S Z, ad armil-
lam circularem R T Y. Ergo vt armilla ad armil-
lam, ſic rectangulum D E B, ad rectangulum D V B.
Sed vt rectangulum D E B, in portione ad rect an-
gulum D V B, ſic rectangulum C D A, in parabo-
la ad rectangulum C F A; & vt rectangulum C D A,
ad rectangulum C F A, ſic D B, ſeù F H, ad F G,
ex ſchol. propoſit. 22. lib. prim. Ergo vt armilla cir-
cularis Q S Z, ad armillam circularem R T Y, ſic
H F, ad F G. Cum vero puncta V, F, ſumpta ſint
arbitrariè; ergo concludemus omnes armillas circu-
lares tubi parallelas armillæ N L P, eſſe ad omnes
armillas circulares exceſſus portionis ſupra