CHAPTER XVIL 

 SHELLS. 



MONG the many wonderful productions of na- 

 ture are the sea shells. How beautifully is 

 the wisdom of God manifested in shaping out 

 and moulding them, and especially in the par- 

 ticular angle which the spiral of each species 

 of shell effects, a valve connected by necessary relation with 

 the material of each, and with its stability, and the condi* 

 ditions of its buoyancy. 



