of the Pacific by the wall of the Cordilleras, but open to the north, both the Mackenzie basin and the Barren Grounds are left to the mercy of the polar winds which blow from that zone of barometric maximum which, like an "arctic wind-divide",[1] separates the minima over the northern Atlantic and the Pacific. Extreme cold, which on the Barren Grounds in January lies between 12° and 16° C. too low according to the latitude, prevails during the whole winter in this area.
And yet in the Mackenzie basin we find a climate that is quite different to that which prevails farther east. In four years out of five wheat ripens at Fort Simpson, a degree more to the north than Eskimo Point, and barley reaches up to the same latitude as Chesterfield Inlet.[2] The tremendous inland sea of Hudson Bay absorbs a large part of the drift ice from Foxe Channel and Fury and Hecla Strait, but permits neither this ice nor that formed in the bay itself to get out at any other point than through the narrow Hudson Strait in the northeastern corner. Thus the bay acts as a huge ice-house throughout the summer and is mainly responsible for the low summer temperatures which create the arctic climate over the Barren Grounds. Even in July the Bay is up to 4° too cold according to its situation, whereas the Mackenzie basin at the same time has a surplus of heat. The isanomal for 0° seems to run a little south of the timber line and parallel to it.
One of the variable factors which contribute towards determining the physical climate in the Arctic and which makes the study of it especially difficult, viz. the situation in proportion to the enormous accumulations of ice,[3] does not trouble us on the Barren Grounds. As a consequence of its situation in the extreme zone of the arctic region the climate on the whole closely approaches the cold temperate. In southern West Greenland there is another transitional zone between the arctic and the temperate belts, and yet there is a striking contrast between this region and the one here described. In southern West Greenland the weather is moist, subject to the influence of the ocean and with fairly mild winters. Over the Barren Grounds the wind blows most of the year from NW., so that between the bitterly cold winters and the cool summers we have an average annual amplitude of about 40° C. and simultaneously a very slight precipitation. This extremely continental character marks an approach to the climatic type of the Mackenzie basin.
Vegetation. Some day, when the flora in the Caribou Eskimo territory is sufficiently known, we will presumably again be able to
