[457.1intra globos Ofeillari debent, ut Ofeillationes omnes evadant 1o-chronz. Nam gravitas(ut in Libro tertio docebitur) decre-feit in progreffü a fuperficie Terre, furfum quidem in duplicataratione diftantiarum a centro ejus, deorfum vero in ratione fim-pliciProp. LIIL Prob. XXXV.

Conceflis figurarum curwilinearum Quadraturis, invenire Dires GUi-bus corpora in datis curzis lineis Ofcillationes femper Tfochronasperagent,

Olcilletur cor-pus Tin curvaquavis linea ST-

RO_ ‚cujus axis

fit OR tranfiens

per virium cen-trum C. Agatur

TX quz curvam

illam in corporis

„JIoco quovis T

contingat, ing;

hac Tangente T-

X capiatur TT

axqualis arcui T-

R. Nam longitu-

do arcus illiusex

figurarum Qua-draturis per Methodos vulgares innotefeit. De pundto Y educa-tur re&a TZ Tangenti perpendicularis.. Agatur CT perpendi-culari illi occurrens in Z,&erit vis centripeta proportionalis rec-

tw 1Z. Q.E.1.

Nam fi vis, qua corpus trahitur de T verfus C, exponatur perredtam TZ captam ipli proportionalem, refolvetur hac in vires

TT,