326 



Mr. L. Lownds on the Thermomagnetic and 



crystalline plate were removed so far as possible by careful 

 rubbing on a fine emery surface. In the end there remained 

 but a slight fracture at one corner. The dimensions of the 

 plate were : length 16 mm., breadth 13*5 mm., and thickness 

 4 mm. A chemical analysis of the bismuth has not yet been 



made. 



Fig. 1. 



Fiff. 2. 



§ 3. Suppose in figs. 1 and 2, OX, OY, OZ are the co- 

 ordinate axes, OABC the crystal and OA the direction of the 

 chief crystallographic axis. Consider throughout the lines of 



