286 



Prof. Anderson and Mr. Bowen on an 



Fig. 1 (a) is drawn on the supposition that the angle of 

 contact is zero. It will be seen that the drop forms two 

 cylindrical lenses, one convex with centre at the point 0', 

 the other (only the lower half of which is present) being 



Fig. 1. 



A 



— « — =- 



(a,) 



vrz- 



B 



A 







__,p 



ih) 



/ 



/' 





J* 



\ 



V 





\ 



-+B 



concave with centre at 0, the point where the glass plate is 

 tangential to the contour of the drop. The upper edge of the 

 drop may be along the line through perpendicular to the 

 plane of the paper, or may be higher up at some point N. If a 



