THE FRIENDLY ARCTIC 177 



house. But it is obvious that if a door in the wall is open and if 

 the interior of the house is being artificially heated, then warm air 

 being lighter than cold, there will be a continual current of heated 

 air going out through the upper half of the doorway, and a cold 

 current from outside entering along the floor. If the door is on a 

 level with the floor or a little below it, the warm air from the house 

 cannot go out through the door, even with the door open, because 

 warm air has no inclination except that of rising. Similarly cold 

 air cannot come in through the door in the floor so long as the house 

 above is filled with warmer air, for two bodies cannot occupy the 

 same space at the same time. It is accordingly never necessary to 

 close a door the top of which is on a level with the floor of the 

 house or lower, and we leave our doors always open. In heating 

 the house, whether by blue-flame kerosene stove, seal-oil lamp, or 

 the bodies and breathing of people, poisons accumulate and venti- 

 lation becomes necessary. So we have a ventilating hole in the 

 roof, depending in diameter on conditions of external temperature, 

 abundance of fuel and on whether people are awake or asleep. 

 The cold fresh air from outside then wells up from the door below 

 into the house as fast as and no faster than is necessary to replace 

 the hot air passing out of the ventilator at the top. 



When the tunnel and door have been excavated, the bedding is 

 passed into the house, and a layer of deerskins with the hair down 

 is spread to cover the entire floor except just where the cooking is 

 to be done. Over this layer we spread another layer of skins with 

 the hair up. The reason for the double insulation is that the 

 interior of the house is going to be warmer presently and people 

 are going to sit around on the floor and later are going to sleep 

 on it, and if the insulation were not practically perfect, the heat 

 from the cooking and from the bodies of the sleepers would pene- 

 trate through the bedding to the snow underneath, and by melting 

 it would make the bedclothes wet. When the temperature of the 

 weather outside, and consequently of the snow inside, is zero Fah- 

 renheit or lower, a double layer of deerskins will prevent any thaw- 

 ing underneath the bed, the snow there remaining as dry as sand 

 in a desert. 



When the floor has been covered and the bedding, cooking gear, 

 writing materials and other things brought in, a fire is lighted. 

 The end to be gained if fuel is abundant is to heat the house until 

 the snow in roof and walls begins to thaw. If the fuel allows it we 

 sometimes bring the temperature temporarily as high as eighty 

 degrees Fahrenheit, and then keep feeling of roof and walls to 



