435 



The weight of each of the alloys experimented with was generally 

 about 260 grms., and that of each crystallization on the average 

 40 grms. lii the last alloy, crystals fit for analysis could only be 

 obtained in the first crystallization. The mother-liquor was, how- 

 ever, crystallized four times, and the last mother-liquor analysed. 



We are indebted to the kindness of Professor Miller of Cambridge 

 for the following determination of the crystalline form of the fore- 

 going alloys : 



Description of the Crystals of Gold and Tin. 



Pyramidal : 



I 72 



50 2'-7. 



201, 112, 114, 



001, 101 = 

 Observed forms : 



001, 102, 104, 304, 

 with very obscure traces of the forms 



502, 401, 203. 



The combination most frequently observed was 



001, 201, 112. 



The angles between normals to the faces, computed from a mean 

 of the best observations, are 



