io8 ESSAYS AND OBSERVATIONS 



itfelf, ior ft ar ting new fads Hkewife, or at 

 leaft of new-modelling the old ones. 

 The method in which the whole af- 

 fair IiAth been condu(5ted, and the 

 jarring and oppofite interefts adjufted, 

 will bed appear by an inftance or 

 two. It is faid, " That, when a body is 

 " thrown up with a double velocity, and 

 " confeqiuntly with a double force, the 

 " reafon why it albends four times its 

 ^' former height, is pLiinly this, that the 

 *' counteradion of gravity, while it has a 

 ** double force to flruggle with, has but 

 " halt the time, in any given fpace, to 

 " produce its effecl, " The natural 

 meaning of which is, that if a body 

 thrown up with any velocity, rifes to a 

 certain height in a given time, a body 

 thrown up with double the velocity ought > 

 to afcend to an equal height in half that 

 time. This indeed would hold true, if 

 the upward motions could be fuppofed u- 

 niform : But, as a body thrown up hap- 

 pens always to be equably retarded, the 

 real fad; comes out to be very different. 



The 



