DISPLACEMENT 



Let the circle A represent the circumference of 

 a perfect sphere. And let the lesser circles within 



Fig- A 



it represent the circumference of smaller indivis- 

 ible spheres. Then, because the lesser spheres are 

 indivisible, their outline cannot be altered to con- 

 form to the outline of the greater circle ; and their 

 closest possible contact with each other leaves inter- 

 stices between them. (Prop. III.) , 



Therefore, a perfect sphere cannot be built up 

 of lesser spheres. And since this will hold good 

 in a greater degree with rectilineal solid bodies, 

 therefore, etc. 



PROPOSITION XI. 



In the transmission of force from one body to 

 another, every intervening body must undergo a 

 change. 



Let Figure A represent the experiment wherein 



Fig A 



17 



