( *«3 ) 
VL A Remark upon the Njn> Opinion relating to 
the Forces of moving Bodies, in the cafe of the 
Collifwn of Non-Elaftic Bodies. By Mr. John 
Eames, F.R. S, 
HE antlent Opinion, and mofl generally enter- 
I . rained, is, that the Forces of Bodies in Motion 
are as their Quantities of Motion, /. e, as their Quanti- 
ties of Matter multiplied by their refpedive Celeri- 
ties. 
2. The new Opinion is, that the Forces of Bodies in 
Motion are as their Quantities of Matter multiplied by 
the Squares of the Velocities ; fo that in equal Mal- 
fes the moving Forces will not be as the Velocities 
themfelves, but as their Squares. 
3. Hence it follows, that a Body moving with five 
Degrees of Velocity, moves with five and twenty Times 
more Force, than when it moves but with one Degree ; 
whereas according to the common Opinion, it has but 
five times as much, i.e. proportional to its Velocity. 
, 4. The latefl: Experiments brought to prove the 
truth of the new Opinion are made upon foft, or 
yielding Subftances. Now thefe have been alrea- 
dy obferved to be a little complicated, and improper . 
for this Purpofe. The proper Ufe of Experiments of 
this kind being rather to difeover, and fettle the Laws, 
which fuch kind of Subflances obferve in the Refiftance 
they make to Bodies moving in them, than the Forces 
themfelves, with which the Bodies move, which ought 
to be determined before hand by fome fimple Experi- 
ment, fit to determine that Matter. 
