W. A. Johnston — Delta of F reiser River. 453 



determined by assuming that the rate of seaward advance 

 of the delta as determined for the past 60 years has been 

 uniform during the time of formation of the delta, and 

 dividing the rate into the distance of advance of the 

 delta. The average distance from the inner edge of the 

 delta along the highland below New Westminster to the 

 seaward front of the delta is about 80,000 feet. Dividing 

 this by 10 feet gives 8,000 years as the age of the Recent 

 delta. It is possible, however, that the rate of advance 

 has varied in the past and that part of the delta above 

 New Westminster was formed in Recent time. Hence 

 these fignires have little absolute value, but they seem to 

 show, nevertheless, that the relationship of sea and land 

 in the Fraser delta region has been nearly if not quite 

 stable for several thousand years and that the last uplift 

 of the land or lowering of sea-level took place probably 

 not more than 10,000 to 12,000 years ago. 



The writer is indebted to the late Commander Mus- 

 grove of the Department of the Naval Service of Canada, 

 under whose direction the soundings in the strait of 

 Georgia were made in 1919, for records of the soundings ; 

 and to Mr. W. H. Boyd, Chief Topographer of the Geolo- 

 gical Survey, Canada, who correlated the soundings in 

 1859 and in 1919 and determined the rate of advance of the 

 delta. 



SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 



1. The Separation of Gallium from Indium and Zinc hy Frac- 

 tional Crystallization of the Caesium-Gallium Alum. — The sep- 

 aration of gallium and indium by this method was briefly 

 described by Uhler and Bro"\\Tiing in this Journal in 1916 (42, 

 389). This method has now been studied .quantitatively by 

 Philip E. B-rowning and Lyman E. Porter. Starting with 7.5 g. 

 of mixed hydroxides containing 26.5 parts of gallium oxide to 

 73.5 parts of indium oxide, they dissolved this in sulphuric acid, 

 added a little more than the theoretical amount of caesium sul- 

 phate, neutralized most of the free acid with sodium hydroxide, 

 ad then crystallized from a volume of 250 cc. The first crop 

 gave a product with 85.1 parts of gallium oxide to 14.9 parts of 



