va ~6 ""Mr. 'Vince on the 'Motion of 
before l conclude, to give the refult of my examination into 
;uthe nature of the experiments which have been made by 
others; which were repeated, in order to fee how far they 
were concliifive in refped to the principles which have been 
t deduced from them. The experiments which have been made 
; by all the authors that I have feen, have been thus iiiftituted* 
To find what moving force would juji put a body at reft in 
: motion : and they concluded from thence, that the accelerative 
: force was' then equal to the fridion; but it is manifeft, that 
any force which will put a body in motion muft be greater 
x than the force which oppofes its- motion, otherwife it could not 
; overcome it ; and hence, if there were no other objection than 
this, it is evident, that the friction could not be very accurately 
obtained; but there is another objedion which totally deftroys 
the experiment fo far as it tends to fhow the quantity of fric- 
tion, ’which is the ftrong cohefion of the body to the plane' 
when it lies at reft ; and this is confirmed by the following 
experiments, ift, A body of 12 f oz. was laid upon an hori- 
zontal plane, and then loaded with a weight of 8 lb. and fuch 
a moving force was applied as would, when the body was juft 
p u t in motion, continue that motion without any acceleration, 
in which cafe the fridion muft be juft equal to the accelerative 
force. The body was then flopped, when it appeared, that the feme 
moving force which had kept the body in motion before, would 
not put it in motion, and it was found neceftary to take off 
4! oz. from the body before the fame moving force would put 
it in motion ; it appears, therefore, that this body, when laid 
upon the plane at reft, acquired a very ftrong cohefion to it. 
adly, A body whofe weight was 1 6 oz. was laid at reft upon the 
horizontal plane, and it was found that a moving force of 6 oz. 
would juft put it in motion ; but that a moving force of 4 oz. 
