LAWS OF DECREMENT. 359 



HEXAGONAL PRISM. 



if, when so applied, we find that the laws of decre- 

 ment producing those planes are simple, we may 

 conclude that we have determined the dimensions of 

 our prism rightly ; but if the ratios we have assigned 

 to the primary edges, suppose those planes produced 

 by irregular and extraordinary laws of decrement, 

 we may conclude that the plane which we have first 

 observed, has resulted from some other law than by 

 1 row of molecules, and we must proceed to assign 

 new dimensions to the prism, in conformity with the 

 new law, by which we now suppose the plane first 

 observed to have been produced. 





