1890 .] 
143 
[Upham. 
of about 90° Fahrenheit ; and the greatest cold of winter is — 30° or 
sometimes — 40°. The annual precipitation of moisture as rain and 
snow is from 20 to 30 inches. It is distributed somewhat equally 
throughout the year ; damaging droughts or excessive rains seldom 
occur. In winter the snow is commonly about a foot deep during 
two or three months, and very rarely it attains an average depth 
of two or three feet. 
Forest and 'prairie . — The Red river basin is crossed by the south- 
western boundary of the forest that overspreads the greater part 
of British America and nearly the entire eastern half of the United 
States. This boundary between forest and prairie, having an al- 
most wholly timbered region on its northeast side, and a region on 
its southwest side that is chiefly grassland, without trees or shrubs, 
runs as follows. From near the junction of the South and North 
Saskatchewan rivers, it passes southeasterly by the sources of the 
Red Deer and the Assiniboine, and over the southwestern slopes 
of Duck and Riding mountains, to the south end of lakes Manitoba 
and Winnipeg. Thence it turns southward and holds this course 
along the east side of the Red river and approximately parallel 
with it, at a distance increasing from fifteen to fifty miles from the 
river, for about three hundred miles, to the upper part- of this stream 
where it flows from east to w'est in Minnesota. Groves of a few 
acres, or sometimes a hundred acres or more, occur here and there 
upon the prairie region beside lakes, and a narrow line of timber 
usually borders streams, as the Red river and its principal tributa- 
ries ; but many lakes and creeks, and even portions of the course 
of large streams, have neither bush nor tree in sight, and occasion- 
ally none is visible in a view which ranges from five to ten miles in 
all directions. The contour of the prairie is as varied as that of 
the wooded region. Within the Red river valley the surface is al- 
most absolutely level; but the adjoining prairie 1 country is undulat- 
ing, rolling and hilly, having in some portions a very rough surface 
of knolls, hills and ridges of morainic drift, that rise steeply 25 to 
100 feet or more above the intervening hollows. The sheet of drift 
covering the greater part of all these areas, whether forest or prai- 
rie, is closely alike, being till or unmodified glacial drift, showing 
no important differences such as might cause the growth of forests 
in one region and of only grass and herbage in another. 
The absence of trees and shrubs in the prairie region has been 
