290 The Pressure of a Blow. [Jan. 26, 



can see that the mass of mild steel surrounding the point of the 

 shell, and pressed into firm contact with it, might by its inertia oppose 

 a powerful resistance to this sudden change of form, and so support 

 the shell during the minute fraction of time which determines whether 

 it or the plate shall go. 



[B.H.] 



