Manchester Memoirs, Vol. Ixii, (191 7) No. 1 11 



If we suppose that the elements of stress are such function? 

 of an arbitrary vector as. I have proposed, we reduce the number 

 of arbitrary elements to three. I am now able to sketch an 

 outline of my proposal of dealing with questions of materia] 

 stresses. 



Consider the case of a body in motion. I shall first regard 

 the (body as rigid, and suppose that the problem is solved on 

 that basis, and that u, v , w , oj„ u y , w v are determined. 



Then consider such equations as 



m(u — v w z + w i>> y — io z y + wys) 



— (to y ' 2 + w~ 2 )x + (t) x d) y y + w v w,z) 



8x 8y 8% ' 



T'hese equations are to be treated as the statical stress 

 equations have been treated, the reversed effective forces being 

 included as " forces," and the corresponding values of the 

 elements oif stress determined as above. 



