148 Mr. A. E. Tuff on on the Constitution of Cryatah. [May 2, 



several fellow- workers, on the possible modes of partitioning space 

 and the types of molecular packing, will eventually lead to a solution 

 of this important question. 



During the researches described in this lecture many thousands of 

 crystals have had to be prepared in a state of perfection and purity, 

 many hundreds of section-plates and prisms cut and ground, and 

 innumerable measurements with the most refined of instruments 

 carried out. But one forgets the labour in the contemplation of 

 knowledge truly gained, and one remembers only the delights of the 

 way, the glorious phenomena of colour which one has enjoyed, and 

 the exquisite beauty of the crystals themselves. 



[A.E.T.] 



