HOW I LEARNED TO HUNT SEALS 275 



First this ice was so weak that the seal could come up 

 whenever he liked and break it by bumping his head 

 against it. He had to do this several times an hour, for 

 a seal has to breath the free air occasionally. He is not 

 a fish with gills that can take oxygen from the water, 

 but a mammal that breathes through nostrils like a dog. 



The fresh water ice with which most of us are familiar is 

 transparent like window glass and almost as hard, but 

 the thinnest sea ice is never transparent. In appearance 

 it is more like ground glass which lets the light through 

 although you cannot see through it. Another difference 

 is that fresh ice is so strong that a big man can walk 

 around safely on a pond covered by an inch of it. An 

 inch of salt ice would not support a puppy, and children 

 cannot play safely on three inches of it. Where lake ice 

 is like glass, sea ice is like ice cream until it finally 

 hardens and toughens with increasing thickness. We do 

 not consider it safe to travel with a dog team and loaded 

 sledge over sea ice less than six inches in thickness. Once 

 we broke through and came near losing all our belongings 

 crossing a stretch of ice five and three-quarters inches 

 thick. We knew the danger and had taken the risk be- 

 cause the strip was only a few yards wide and we thought 

 we could hurry across in safety. Our dogs did get across 

 and the ice broke just as the front end of our sled touched 

 the solid floe, so that only the back end of the sled got 

 into the water. We would have lost the whole load had 

 the ice broken when the sled was two feet farther away 

 from the floe. 



This mushiness of the sea ice in the fall enables the 

 seals to continue their travels in the ocean underneath it 

 until a thickness of four inches has been attained. After 

 that they can no longer smash their way up to the air, 



