[61.] PROPOSITIO VI.

[62.] PROPOSITIO VII.

[63.] PROPOSITIO VIII.

[64.] PROPOSITIO IX.

[65.] Conoidis parabolici ſuperficiei curvæ circulum æqualem invenire.

[66.] Sphæroidis oblongi ſuperſiciei circulum æqualem invenire.

[67.] Sphæroidis lati ſive compreſſi ſuperficiei circulum æqualem invenire.

[68.] Conoidis hyperbolici ſuperficiei curvæ circulum æqualem invenire.

[69.] Curvæ parabolicæ æqualem rectam lineam invenire.

[70.] PROPOSITIO X.

[71.] PROPOSITIO XI.

[72.] HOROLOGII OSCILLATORII PARS QUARTA. De centro Oſcillationis.

[73.] DEFINITIONES.

[74.] I.

[75.] II.

[76.] III.

[77.] IV.

[78.] V.

[79.] VI.

[80.] VII.

[81.] VIII.

[82.] IX.

[83.] X.

[84.] XI.

[85.] XII.

[86.] XIII.

[87.] HYPOTHESES. I.

[88.] II.

[89.] PROPOSITIO I.

[90.] PROPOSITIO II.