CONTENTS 
Physics. — Positive Ray Analysis of Magnesium . . . By A. J. Dempster 45 
Physics. — The Energy Content op the Diapason . . . . By C. Barus 47 
Genetics. — A Preliminary Note on the Results of Crossing Certain Varie- 
ties of Nicotiana Tabacum 
By W. A. Selchell, T. H. Goodspeed and R. E. Clausen 50 
Chemistry. — The Correlation oe Compound Formation, Ionization and Solu- 
bility in Solutions. Outline op a Modified Ionization Theory 
By J. Kendall 56 
Physics— The Pelter Effect . . . . By E. H. Hall 62 
Mathematics. — On the Roots of Bessel's Functions . .By J. H. McDonald 66 
