CONTENTS OF VOL. XV. FIFTH SERIES. Vll 



Prof. S. P. Thompson on Polarizing Prisms 435 



Proceedings of the Geological Society : — 



Mr. H. W, Monckton on the Bagshot Sands 436 



Prof. T. G. Bonney on Boulders of Hornblende Picrite 



near the Western Coast of Anglesey 437 



Mica Pilms for Polarizing Purposes, by H. G. Madan 437 



To Cut a Millimetre-screw, by Charles K. Wead 438 



On the Condensation of Fluids on Solid Bodies, by Eilhard 



"Wiedemann 440 



EKRATA IN VOL. XIV. 



Page 297, line 32, for A+u' is A+w'{&c. 

 read A+m' is A+w'- |&c. 



— - line 33, for wV-+?(B-A) 



readw'+w"-?(B-A) 

 n 



