[ 70 ] 
only make L the gteateft Length to which the Spring 
can be drawn out beyond its natural Situation, with- 
out Prejudice to its Elafticity, / any leffer Length to 
which the Spring is drawn outwards, T and p the 
Forces, which will keep it from reftoring itfelf when 
drawn out to thofe Lengths refpe&ively, and the 
Propofition will equally hold good : As it will alfo, 
if the Spring be fuppofed to have been already 
drawn outwards to the Length /, and, in reftoring 
itfelf, to draw the Body after it : Only, in this lat- 
ter Cafe, V, the initial Velocity in the Propofition, 
will now be the final Velocity, as in Scholium IV. 
Scholi um VI. 
Our Propofition equally holds good, when the 
Spring is of any Form whatfoever, provided L be 
always underftood to be the greateft Length it can be 
bent or drawn to from its natural Situation, / any 
leffer Length, and T, p, the Forces which will con- 
fine it to thefe Lengths. For Dr. Hook’s Principle 
extends to Springs of any Form. 
I have been at the Trouble of drawing fo great 
a Number of Corollaries from this Propofition, be- 
caufe, in the Controverfy about the Force of Bodies 
in Motion, I have obferved both Parties to fupport 
their Opinion by Arguments taken from the The- 
ory of Springs ; and I was willing impartially to 
furnifh them both with means to examine into the 
Truth or Falfhood of one another’s Reafonings. I 
had Thoughts myfelf of making ufe of fome of thefe 
Corollaries for that Purpofe, being far from think- 
ing, that the Difpute is about Words only ; but this 
Letter is already drawn out to too great a Length 5 
and 
