35 3 Mr . sm baton’s Fundamental Experiments 
ot llick (luppole the fame fize as the rods) turn afide the rod 
gh with the right-hand, carrying the body D upwards till the 
ftick is upon the mark w, as fuppofe at o ; there hold it, and 
with the left fet the body C perfectly at reft ; in which cafe the 
rod ef will be over the mark t ; then fuddenly withdraw the 
ftick, in the direction that the rod gh is to follow it, and the 
Spring ot the body D, impinging upon that of the body C, 
they will be both bent, and alfo reftored ; and the body C will 
fly off, and mount till its rod ef covers the mark x ; the rod of 
tiie flunking body D remaining at reft upon its proper mark of 
ii ft o’, till the body C returns, when the body D will fly off in 
he fame manner ; the two bodies thus rebounding a number of 
times, loling a part of their vibration each time ; but l'o nearly 
is the theory of elaftic bodies fulfilled hereby, that the Angle ad- 
vantage of originally puffing the rod gh beyond the mark w, by 
the thicknefs of the ftick, or its own thicknefs, is fufficient to 
carry the rod of the quiefeent body C completely to its mark at. 
There are feveral other experiments that may be made with 
this apparatus, in confirmation of the doctrine of the collifion 
of elaftic bodies ; which being univerlally agreed upon, and 
well known, it is needlefs further to dwell upon here; but 
refpe&ing the application to non-elaftic foft bodies, it is far 
moie difficult to come at a fitnefs of materials for this kind of 
experiments, than it is lor thole fuppofing perfectly elafticity. 
The conclufions, however, may be attained with equal cer- 
tainty. 
I'OR TRIALS ON NON- ELASTIC SOFT BODIES. 
For this puipofe the ratchets mull be applied and put in 
order as before deferibed, and the fprings being both put to 
their point of reft, let the body D be put to its mark w in the 
fame 
