182 A. M. Edwards— Hudson River "Fiord." 



gravel deposits, similar in many ways to the long, winding 

 ridges to which the name osar has been applied. 



Marginal lakes. — Along the northern margin of the Malas- 

 pina glacier wherever a mountain spur projects into the ice, the 

 rocks become warmed, and radiating heat, causes the adjacent 

 border of the glacier to melt away. This forms a valley which 

 becomes a line of drainage. When the streams, following the 

 sides of a mountain spur projecting into the glacier, come to- 

 gether, a lake is formed which discharges through a tunnel in' 

 the ice. When the glacier passes the mouth of a lateral valley 

 the drainage is checked and a lake formed. There are several 

 lakes of this character about the Chaix hills. There are other 

 methods by which the great glacier acts as a dam and cause 

 lakes to form, but we have not time to trace out all of their 

 histories. 



These marginal lakes on the north side of the Malaspina 

 glacier are situated at an elevation of from a thousand to fifteen 

 hundred feet on the sides of the mountains, and receive the 

 debris brought down by tributary streams, which is built into 

 deltas and terraces. When the glacier melts away these de- 

 posits will be left as irregular terraces on the mountain side. 

 Lakes will be formed about the same mountain spurs, again 

 and again, as the surface of the ice is lowered, thus making an 

 irregular record with considerable vertical range. It seems to 

 me that similar records should be found on the southern slopes 

 of the mountains of New England, and other regions, which 

 were formerly covered by ice-sheets, analogous to the Malaspina 

 glacier. 



Photographs of the magnificent scenery of the St. Elias 

 region were exhibited at the close of the lecture. 



Art. XXI. — Hudson River "Fiord" ; by Arthur M. 

 Edwards, M.D. 



I have been for sometime investigating the deposit thrown 

 down during the Champlain period in the Hudson River, New 

 York, more especially to find out if it is the same as that of 

 the bay of Newark, N. J., and I have decided that they are 

 different ; that of Newark being newer than that of the 

 Hudson River. But I have been called upon to examine the 

 soundings from the Hudson River "Fiord" made by Mr. A. 

 Lindenkohl of the TJ. S. Coast Survey which he has kindly 

 furnished to me and they are with the following results. In 



