178 THE FRIENDLY ARCTIC 



watch the progress of thawing. This, of course, is most rapid in 

 the roof as the liot air accumuhites against it, and usually the lowest 

 tier of blocks near the floor does not thaw at all. Thawing pro- 

 ceeds without dripping, because dry snow is the best sort of blotter 

 and soaks the water into itself as fast as it forms. When the 

 inner layer of the roof has become properly wet with the thawing 

 and the walls damp to a less degree, we either put out the fire or 

 make a large hole in the roof, or both, and allow the house to freeze. 

 This glazes it on the inside with a film of ice, giving it far greater 

 strength, with the further advantage that if you rub against the 

 glazed surface scarcely anything will adhere to your clothing, 

 while from the dry snow before the glazing takes place you would 

 get your shoulder white, with a good deal of snow perhaps falling 

 on the bed. 



Now the house is so strong that without taking special care 

 any number of men could climb on top of it. Polar bears may 

 and occasionally do walk over these houses and I have never known 

 of one breaking. Their strength, however, is somewhat the same 

 as the strength of an eggshell, and while they are difficult to crush 

 with pressure, they are easy to break with a blow. A polar bear 

 has no trouble in getting in if he wants to, for one sweep of his 

 paw will scratch a great hole. 



If the house was built at fifty below zero, each block in the wall 

 was of that temperature and contained w'hat we may unscientifi- 

 cally speak of as a great deal of "latent cold." To neutralize this 

 it is necessary to keep a temperature of about sixty degrees Fahren- 

 heit for a considerable time. Snow is so nearly a non-conductor 

 of heat that when the "latent cold" has once been neutralized, the 

 heat of our bodies keeps the temperature well above the freezing 

 point even with the hole in the roof open for ventilation. But if 

 the weather gets a little warmer than when we made camp, our 

 body heat may be too great or the cooking may raise the tem- 

 perature high, and the roof will begin to melt. This we take not 

 so much as a sign that the house is too warm as that the roof is 

 too thick, so we send a man out with a knife to shave it thinner, 

 perhaps from four down to two inches, giving the cold from outside 

 a chance to penetrate and neutralize the heat from within, stopping 

 the thawing. It may happen the next day that the weather turns 

 colder again, and in that case hoar frost begins to form on the 

 roof and drops in the form of snowfiakes on the bed. That is a 

 sign that the roof is now too thin and a man goes out with a 

 shovel and piles on enough soft snow to blanket it. 



