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ſome other time, namely, when you ſhall ſee the matters concer

ning local motion demonſtrated by our Academick; at which

time you ſhall find it proved, that in the time that the one movea

ble falls all the ſpace C B, the other deſcendeth by C A as far

as the point T, in which falls the perpendicular drawn from the

point B: and to find where the ſame Cadent by the perpendi

cular would be when the other arriveth at the point A, draw from

A the perpendicular unto C A, continuing it, and C B unto the

interfection, and that ſhall be the point ſought. Whereby you

ſee how it is true, that the motion by C B is ſwifter than by the

inclination C A (ſuppoſing the term C for the beginning of the

motions compared) becauſe the line C B is greater than C T,

and the other from C unto the interſection of the perpendicular

drawn from A, unto the line C A, is greater than C A, and

therefore the motion by it is ſwifter than by C A But when we

compare the motion made by all C A, not with all the motion

made in the ſame time by the perpendicular continued, but with

that made in part of the time, by the ſole part C B, it hinders

not, that the motion by C A, continuing to deſcend beyond, may

arrive to A in ſuch a time as is in proportion to the other time,

as the line C A is to the line C B. Now returning to our firſt

purpoſe; which was to ſhew, that the grave moveable leaving

its quieſcence, paſſeth defcending by all the degrees of tardity,

precedent to any whatſoever degree of velocity that it aequireth,

re-aſſuming the ſame Figure which we uſed before, let us remem

ber that we did agree, that the Deſcendent by the inclination C

A, and the Cadent by the perpendicular C B, were found to have

acquired equal degrees of velocity in the terms B and A: now to

proceed, I ſuppoſe you will not ſcruple to grant, that upon ano

ther plane leſs ſteep than A C; as for example, A D [in Fig. 5.]

the motion of the deſcendent would be yet more ſlow than in the

plane A C. So that it is not any whit dubitable, but that there

may be planes ſo little elevated above the Horizon A B, that the

moveable, namely the ſame ball, in any the longeſt time may

reach the point A, which being to move by the plane A B, an infi

nite time would not ſuffice: and the motion is made always more

ſlowly, by how much the declination is leſs. It muſt be therefore

confeſt, that there may be a point taken upon the term B, ſo near

to the ſaid B, that drawing from thence to the point A a plane,

the ball would not paſs it in a whole year. It is requiſite next

for you to know, that the impetus, namely the degree of velo

city the ball is found to have acquired when it arriveth at the

point A, is ſuch, that ſhould it continue to move with this ſelf-ſame

degree uniformly, that is to ſay, without accelerating or retarding;