CONTENTS 



Original Papbrs 



Page 



Physics — The relation between birefringence and stress in various types ,of 

 glass. L. H. Adams and E. D. Wilijamson 609 



Zoogeography — Discontinuous distribution among the echinoderms. Austin 

 H. Clark - j 623 



Abstracts 



Geodesy. 626 



Apparatus . • 626 



Physics 626 



Inorganic Chemistry 628 



Analytical Chemistry 630 



Geology 631 



Entomology 638 



Ceramic Chemistry 640 



Radiotelegraphy 641 



Proceedings 



Philosophical Society 642 



Scientific Notes and News. . . '. 645 



