[47.] Christiani Hugenii C. F. ILLVSTRIVM QVORVNDAM PROBLEMATVM CONSTRVCTIONES. Probl. I. Datam ſphæram plano ſecare, ut portiones inter ſe rationem habeant datam.
[67.] PROP. III. THEOREMA. Dico triangulum B A P, & trapezium A B I P ſimul,
eſſe ad trapezium A B I P, ut duplum trapezii
A B I P ad polygonum A B D L P.