302 On the Measure of - 
draw the diagonal AIT; we shall have 2 
diagram of the construction described above 
by M. Laplace ; and, if I understand him 
right, he concludes, that if the forces of E 
and F are respectively as the squares of their 
velocities, AI must be the resulting direction 
of A, and the square of its velocity must be 
to Al as AB*: AG. If, by the force of a | 
body in motion being as the square of its 
velocity, it were meant, that the pressure 
exerted in bringing it to rest in a given time 
must be as the square of its velocity, the 
result must no doubt be such as M. Laplace 
describes. I cannot find, however, that this 
meaning has ever been applied to the prin- 
ciple in question. Such a hypothesis could 
not be entertained, indeed for a moment, 
without setting aside the incontrovertible ex- 
planations and conelusions of Galileo. In 
answer to the objection implied, in the reason- 
ing of M. Laplace, against the force being 
as the square of the velocity, I can only © 
repeat, what I have already so often repeated, 
that it is not the pressure exerted in a given 
time, but the pressure exerted through a given 
space, that is understood to be universally as 
the mass into the square of its velocity; and 
I may add that there is nothing hypothetical. 
in this conclusion.—Being derived from an 
~—— 
a ee 
