merited by snap fasteners or eyelets for lacing in case the slide 

 fasteners fail to work. The bag should have a hood and scarf 

 attachment so that the sleeper's mouth and nose are out of the bag. 



Do not sleep with the head inside the sleeping bag. Moisture 

 from the breath will ice its interior. Wear only the minimum of 

 clothing in the bag and never wear damp underwear. If neces- 

 sary, change to dry underwear before using the sleeping bag. If 

 dry underwear is not available, it is best to bed down in the nude. 

 In very cold temperatures, hoarfrost cannot be removed easily. 

 Care must be taken to keep its formation down to a minimum. Be- 

 cause perspiration cannot be entirely prevented, open the bag im- 

 mediately upon arising and pump air in and out to remove the 

 moist air and reduce the temperature inside the bag. Arctic bags 

 now being issued have cotton liners which can be removed and 

 washed, thus helping to keep the bags themselves clean. Air the 

 bag as frequently as possible. Should the fabric become torn, re- 

 pair it at once to avoid loss of feathers upon which warmth de- 

 pends. 



Never place the sleeping bag directly on snow or any other cold 

 surface. Generally, a mat will be provided to place under the bag. 

 If this is not available, spruce or fir boughs and grass make handy 

 insulators. Before getting in the bag, puff it out by shaking it 

 so that there will be plenty of dead-air space in the down. In 

 mosquito country in summer, netting stretched over the head of 

 the bag is necessary for undisturbed sleep. 



FUNCTION AND DESIGN OF COLD WEATHER CLOTHING 



Good clothing and its proper use are more important in cold 

 country than anywhere else in the world. If the proper technique 

 and equipment are used, a man can work safely and comfortably 

 even at very low temperatures. On the other hand, subzero 

 weather is brutal to men who are poorly equipped. The Arctic 

 does not treat men well. If one underestimates the dangers and 

 fails to wear adequate clothing, or worse, fails to use adequate 

 clothing properly, he may suffer the loss of a hand or foot, or even 

 risk death. 



FUNCTION 



The primary function of clothing is to shut in body heat and 

 keep the body warm. Heat is transferred from a warmer object 

 to a colder one until the temperature of the two becomes nearly 

 the same. As insulation, clothing prevents, or rather slows down, 



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