The usual idea of the amount of clothing necessary to keep the body warm and to prevent freezing in extreme cold is erroneous. It is not so much a question of cold as the degree of dampness on the body surface which is affected _by_ the cold. Nearly every death from freezing is caused by either getting too warm and then wet through perspiration or accidental immersion in water. The former can be avoided by having the clothing sufficiently loose to allow good circulation of air and by thus _keeping uncomfortably cool_ the tendency toward perspiration is overcome. While quiet or physically inactive one may wear much clothing as there is little danger of freezing, there being no dampness present, but if one is active and perspiring and is then quiet there is great danger. When any kind of moisture gets on the body there is only one way to get rid of it--by the body heat. Clothing does not warm one, it only _retains_ heat made by the body. The drawing away of heat reduces one’s vitality as well as affecting the temperature of the body. Where one is physically active it is advisable to wear ordinary weight warm winter clothing of the temperate zone. Of materials wool is best next the body, except in Arctic work where a suit of silk is worn under the fur garments to prevent chafing. Two wool union suits, loosely fitting, will be found enough. The pants should be of Mackinaw which is warm, wearable, and to a certain extent water repellent. A flannel shirt or Pontiac shirt comes next and for use when one is inactive and apt to become chilled a heavy sweater coat with convertible collar is indispensable. To break the wind a parka can be pulled over head and trunk. The parka is a garment made like a large hooded shirt coming to the knee. The edge of the face opening in the hood has a ruff of wolverine, wolf, or bear to protect the face. Wolverine is by all odds best as it is the only fur upon which the breath will not congeal. The garment is the most practical yet devised for very cold work. For use in the Arctics it is made of squirrel or deer skin worn with the fur outside and it is lined with the fur of some animal which will allow it to slip on and off easily. The drill parka which is used to break the wind and which is of particular interest to us is made on the same model only larger as it is at times worn as the outermost garment of all. The fur garments are seldom used by those who are experienced when working on the trail, they are held in reserve until camp is reached. If in actual exercise the parka would be too hot and would cause perspiration to start.