106 PROCEEDINGS OP THE AMERICAN ACADEMY 



Crystalline Form of Antimonious Oxichloride (SbOCl). 

 Prepared by Schaeffer's Method. 



MONOCLINIC StSTEM. 



Forms \nO\, \0n\, ^001^ 

 Fig. 7, Plate I. 



Angles Measured. 

 Between normals, — 



110 on TIO 98» 2' 



Oil „ OIT 107° 14' 



110 „ 001 100° 8' 



001 „ TTO 79° 52' 



From these we calculated : — 



Clinodiagonal, a = 0.8936 



Orthodiagonal, b = 1 



Vertical, c = 0.7587 



Angle of Axes, =76" 31' 



By referring to page 97, it will be seen that these crystals are closely 

 isomorphous with those of the monoclinic, antimonious iodide. We 

 examined them also with a polarizing microscope, and found that, when 

 the light passed normally to the prismatic faces, the principal optical 

 sections rbade angles of 40'^ and 50°, respectively, with the prismatic 

 edges. 



The following analyses were made by Mr. Richardson. In the first 

 three, the oxichloride was decomposed by boiling over it a solution of 

 pure sodic carbonate. In the last, it was dissolved in a concentrated 

 aqueous solution of tartaric acid. 



Analyses of SbQCl. 

 Prepared by Schaeffer's Process. 



Mean value 20.37 



Theory Sb = 120 20.70 



