Proceedings at the Meetings. 513 
8. On Radio-active Rain. By C. T. R. Wilson, M.A., Sidney 
Sussex College. 
9. On the increased conductivity of air produced by its passage 
through water. By Professor J. J. Thomson, Trinity College. 
May 19 th , 1902. 
In the Optical Lecture Room. 
Professor Macalister, President, in the Chair. 
The following Communications were made : 
1. Some observations on Protandry and Senescence in Flabellum. 
By J. Stanley Gardiner, M.A., Gonville and Caius College. 
2. A note on the dispersive power of running water on Skeletons : 
with particular reference to the skeletal remains of Pithecanthropus 
erectus. By W. L. H. Duckworth, M.A., Jesus College. 
3. The Coral Reefs of Zanzibar. By C. Crossland, B.A., Clare 
College. 
4. On an attempt to detect the Ionisation of Solutions by the 
action of Light and Rontgen Rays. By J. A. Cunningham, St J ohn’s 
College. 
5. On the influence of molecular attraction on collisions. By 
O. W. Richardson, B.A., Trinity College. 
6. On the influence of Ultra-Violet Radiation on the discharge in 
a Vacuum Tube having a polished zinc electrode. By W. C. Baker. 
7. On the variation of double refraction in strained glass with 
wave length. By L. IST. G. Filon, B.A., King’s College. 
