“PHYSICAL ano LITERARY. 97 
_ pretty plaufible, and good ‘enough to. pafs.up- 
on Germans and other foreigners ; efpecially 
if they were {trangers to the Engii/h language. 
Another allowable artifide to deceive the ad- 
verfaries, is:in endeavouring to make them 
believe, that all the world knows, that 
“when bodies move through a fluid, or 
‘any; foft matter, a double force produces.a 
“< quadruple effect.” IPf the word effec were 
taken -its moft proper fenfe, for the force 
communicated to the fluid or foft matter, by 
the moving body, ‘this could never exceed 
the force of the body. A double force could 
never produce any more than a double effect 
in its own direétion. All the world indeed 
may know, that when a body ftrikes upon 
clay or other fuch foft matter, a double force 
may produce a quadruple impreffion.’ But 
‘then, this can only happen in: fuch ‘cafes, 
where no other refiftance is worth the mind- 
ing, but that arifing from the cohefion of 
the matter, in the manner above explained. 
Bas. a ball moves through a fluid, the re- 
fiftance proceeds, almoft entirely, from the 
t ) 
denfity or nertia; and, the denfity being gi- 
en, this refiftance muft increafe as the {quares 
of the velocity. In this cafe, it would be a 
N vain 
