SCENERY AND TOPOGRAPHY 



shallow glacier-cut depression extending along the hin- 

 terland from Cape Barne to Cape Royds and beyond. 

 Blue Lake was about six hundred yards long, the others 

 being much smaller. Green Lake was about one hundred 

 yards across and about five feet deep. Below the ice 

 was found a reservoir of liquid brine with the low 

 temperature of 21° F. The temperature of the ice 

 at the bottom was —2° F., w^hile it was —23° F. 

 near the surface. Clear Lake was a little larger, and 

 the ice was eight feet thick. At this lower level the 

 ice was +29° F. while the air outside was about 

 — 10° F. There was four feet of water at the bottom 

 with a temperature of +35° F. Blue Lake w^as fif- 

 teen feet deep, and at the bottom growing algae were 

 found which contained living rotifers (see p. 218). 

 This indicates that the suspension of animation in these 

 organisms must extend over many seasons, for it can 

 be only very rarely that Blue Lake melts to the bot- 

 tom. Farther south, near Cape Barne, is Sunk Lake, 

 whose ice surface was twenty feet below sea level and 

 whose floor w^as some fifty feet below the sea, which 

 was only one hundred and fifty feet distant. Ice-Dam 

 Lakes on Cape Evans, resembling in miniature the 

 Glenroy Lakes of Scotland, are described in the writ- 

 er's large monograph. 



Debris Cones. — A few days after our arrival at Cape 

 Evans the geologists were advised to inspect what our 

 informants described as ''little volcanic craters," which 

 were seriously stated to be parasitic cones on the low- 

 est slopes of Mount Erebus. These cones were scat- 

 tered all over the rock platform between the low 



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