. .. 



9. A solid body if conceived to be 



particles which are held together by 



.- appears to be a wife hypotbsa4, 

 ts shew that tiny body 



and smaller ; 



to overcome the mutual action of the parts of the body. 



which the nartkles retain in- 

 Me positions with respect to each other. No bo*' 



verjr body yields more or less to 

 ich act on it. It, then, tn anv case this com- 

 pressibility is of a sensible magnitude, we snail suppose that 

 the body has assumed its figure of equilibrium, and than 

 consider die point* of application of the forces as a system of 

 invariable form. By body, hereafter, we mean rigid bo 



11. a force acts on a body the effect of the force 



will IN- unchanged at whatever point of its direction we smp- 



i i ( .! ^ -t 



ThU 



of action ; it is lawman as 

 i or as an experimental fact. \\ may shew the 



. involve. I in th- axiom, by the follow* 

 process. 



ix>se a body to be k - 'piilibrium by a 



oneofwhiri. -rcc P applied at 



Take any point B which lies on 



tin .1 t "this force, and suppose B so coo- 



distance A/iu unchange- 



rcea, 



.il in i n:\_i.itudeandactinff inoppo- 

 o straight line A J5, it seems 

 to change is made in the eff. 

 lorce P at A. Let us now asttfsw ih 



it 11 trill nt'ulrnltM eack o/Ar, a*d 



fort be removed wMtmt dithtrbitg (fa 



>,; then there remains the 



force P at 11 producing the same effort cs when 



