Structure of Silver Crystals. 

 Fig. 2. 



87 



p is the density of silver (10*50) and A the atomic weight 

 (107"93). Nis the number of atoms in a gramme equivalent 

 (61*5 x 10 22 ), and d m is given in the table. Inserting these 

 values, 



n = 0'50002, or £, 



Thus the face-centred cubic lattice explains the whole 

 series of experiments, and we come to the conclusion that 

 the atoms in the silver crystals are arranged in the simple 

 face-centred lattice. 



The arrangement is the same as that previously found by 

 W. L. Bragg for copper crystals *. 



In conclusion, I wish to thank Professor W. H. Bragg and 

 Mr. W. L. Bragg for valuable information with regard to 

 the methods of the crystal analysis, Professor W. C. Brogger 

 for his kindness in lending me the crystals and the goniometer 

 on which the Rontgen-ray spectrometer was mounted, and 

 Professor V. Goldschmidt for helpful advice with regard to 

 nrystal work in general. Finally, my thanks are due to 

 Mr. Harald K. Schjelderup for his assistance in making the 

 readings. 



Christiama, Oct. 20, ] 915. 



* W. L. Bragg, " On the Crystalline Structure of Copper," Phil. Mag. 

 vol xxviii. p. 355 (1914). 



