Bodies ajfeBed by 'f riction. 1 6p 
ftage was then adjufted to the fpace correfponding to f > upon 
fuppofition that the fpaces defcended through were as the 
Squares of the times, and it was found to agree with the time ; 
the ftage was then adjufted to the fpace correfponding to 2 ", 
upon the fame fuppofition, and it was found to agree with the 
time; the ftage was then adjufted to the fpace correfponding 
to 1 ", and was found to agree with the time. 
Exp. 4 . A fourth body was then taken and laid upon the 
horizontal plane, and a moving force applied, which defcended 
55 inches in 4" \ the ftage was then adjufted to the fpace 
through which it ought to defcend in 3", upon fuppofition 
that the fpaces defcended through were as the fquares of the 
times, and it was found to agree, with the time ; the ftage was 
then adjufted to the fpace correfponding to 2", upon the fame 
fuppofition, and was found to agree with the time ; laftly, the 
ftage was adjufted to the fpace correfponding to i' ; , and it was 
found. to agree exactly with the time. 
Befides thefe experiments, a great number of others were 
made with hard bodies., or thofe whofe parts fo firmly cohered 
as not to be moved inter fe by the friftion ; and in each experi- 
ment bodies of very different degrees of friction were chofen, 
and the refults all agreed with thofe related above ; we may 
therefore conclude, that the friftion of hard bodies in motion is a 
uniformly retar ding force. 
But to determine whether the fame was true for bodies when 
covered with cloth, woollen, &c. experiments were made in 
order to afcertain it ; when. it was found in all cafes, that the 
retarding force increafeo with the velocity ; but, upon covering 
bodies with paper, the confequences were found to agree with 
thofe related above. 
Vox. LXXV. ;,2 
