[141.] Experimentum.

[142.] CAPUT XVII. De Acceleratione & Retardatione Gravium. Definitio 1.

[143.] Definitio 2.

[144.] CAPUT XVIII. De deſcenſu Gravium ſuper plano inclinato.

[145.] Experimentum 1.

[146.] Experimentum 2.

[147.] Machina, Qua corporum Cadentium velocitates conferuntur.

[148.] Experimentum 3.

[149.] CAPUT XIX. De Oſcillatione pendulorum. Definitio.

[150.] Experimentum i.

[151.] Experimentum 2.

[152.] Experimentum 3.

[153.] Experimentum 4.

[154.] SCHOLIUM I. De motu in Cycloide.

[155.] SCHOLIUM 2. De Centro oſcillationis determinando.

[156.] SCHOLIUM. 3. In quo quædam in boc capite memoratæ Cycloidis proprietates demonſtrantur.

[157.] SHOLIUM 4. De linea celerrimi deſcenſus.

[158.] CAPUT XX. De Projectione Gravium.

[159.] Machina Qua demonſtrata de corporum projectione confirmantur.

[160.] Experimentum.

[161.] Definitio.

[162.] CAPUT XXI. De Viribus Centralibus.

[163.] Definitio 1.

[164.] Definitio 2.

[165.] Definitio 3.

[166.] Machina

[167.] Experimentum 1.

[168.] Experimentum 2.

[169.] Experimentum 3.

[170.] Definitio 4.