Proceedings Am. Philos. Soc. Vol. XLVII. No. 189 



Map I 



Coast Survey map of the North Pacific Ocean, showing the deep trenches in the sea bottom dug out by earthquakes in uplifting the Aleutian, Kurile and Japanese Islands. In the con- 

 tour lines 4 points denote a depth of 4,000 fathoms, 3 points 3,000 fathoms, the continuous dash 2,000 fathoms and the continuous line near shore 100 fathoms. 



