Chap. 9. 4 Trutife ef B O D I E S. 9\ 



from encreafing, it would in time arrive to exceed any particular 

 velocity ; and by confcqucnce, the proportion which the mover 

 hath to the medium: bccaufe of the adding {till a determinate 

 parrtoics velocity) concluding plainly that ic is impoffible, 

 motion fliould increale for ever, without coming to a period. 



Now the impreflion which falling weights do make, is of 

 two kinds ; for the body into which impretfion is made, either certain pr- 

 can yieM backward, or it cannot. If ic can yield backward, b!cm;refoJved 



ff. j . . /- /i i i concerning the 



tnen the tmprenion made is a motion: as we tec a Itroke with a prcportionof 

 racket upon a ball, or with a pail-mail beetle upon a bowl < n e moving 



* _ t /* i r\ 1 it A2"ntS COITi'dl* 



maketh it flic from K. But it the Itrucken body cannot yield red to their 

 backwards, then it maketh it yield on the fides. And this, in di- 

 vers manners : for if the fmittcn body be drieand brittle, it is 

 fubjc-iVto break it, and make the peices flie round about: buc 

 if it be a tough body, it fqueefeth it into a larger form. 



But bccaufe the effe<5t in any of thefe wayes is emim ntly 

 greater then the force of the Agent fccmeth to be ; it is worth 

 our labour to look into thccaufes of it. To which end we may 

 remember how we have already declared that the force of the 

 velocity is eqiull to a reciprocal! force of weight in the virtue 

 movent : wherefore the effect of a blow that a man giveth with 

 a hammer, dependcth upon the weight of the hammer, upon the 

 velocity of the motion, iind upon the hand, in cafe the hand ao 

 companiech the blow. But if the motion of the hand ceaieth 

 before ( 33 when we throw a thing,) thenoncly the velocity and 

 the weight of the hammer remain to be confidcrcd. Howfoever, 

 let us put the hand and weight in oje fum me which we may 

 equalize by feme other virtue or weight. Then let us confidcr 

 thie way or ipace, which a weight lying npon the thing is to go 

 forwards to do the fam? efFc& in the fame time as the percufifk>;i 

 doth. And whatcxccrTe the line or the blow ; hath over the line 

 of that way or ipace ; fuch an exccflfe we muft adde of equal I 

 weight or 'force, to the weight \ve had already taken* And the 

 weight com pofed of both; will be a fit Agent to make the like 

 imprcffion. This Problcme was propofed unto me by that wor- 

 thy religious man, Father Merfenius : who is not content with 

 advancing learning by his own induflry and labours; but be- 

 fidcs, is alwayes (out of his generous affection to vericy ) inci- 

 ting others to contribute to the publick fto:k of it. 



He propolcd to me likewile this following queftion, to wic, 



vvhy 



