DEFINITIONS. 



15 



Fig. 32. 



Fig. 33. 





The right rhombic prism, fig. 32, and right oblique 

 angled prism, fig. 33, have each two greater and two 

 lesser axes. The greater axis, a b, passes through the 

 solid angles which terminate the acute edges of the 

 prism, and the lesser, c d, through those which ter- 

 minate the obtuse edges of the prism. They have also 

 the prismatic axis, ef. 



Fig. 34. 



The oblique rhombic prism has, besides the pris- 

 matic axis, i k, fig. 34, a greater, a lesser, and two 

 transvere axes. The greater axis is that which passes 

 through the two acute solid angles of the prism a, b ; 

 the lesser that which passes through the two obtuse 

 solid angles of the prism c, d, and the tranverse, 

 those which pass through the lateral solid angles, 



