128 Tlic American Geologist. February, iws 
and of forestry, witli notes of luiropeaii countries, by Jolm Gififord. 
The volume is completed with mining statistics for 1896, the catalogue 
of publications of the survey, and an index. w. u. 
Report on ttw Dooixri/nt, Kazan a)id Fei\i^iiso)i RivfrsajidtlicNortJi- 
ivest Coast of Hudson Bay , and on Tivo Overland Routes from Hudson 
Bay to Lake Winnipeg. By J. Burr Tyrrell. Part F, of the Annu- 
al Report of the Geological Survey of Canada, vol. IX, for i8g6. Pages 
218, with eleven plates and three maps. Ottawa, 1897. 
The routes of travel here described extend across an area of about 
200,000 square miles, from near the east end of lake Athabasca north- 
ward and eastward to Chesterfield Inlet and the west side of Hudson 
hay. The explorations were carried on in the years 1893 and 1894, the 
author's return from each expedition being in winter by sledging over 
frozen rivers and lakes between Fort Churchill and Winnipeg. The 
country consists mainly of granitic rocks and granitoid gneisses, of 
Laurentian age, with several large Huronian tracts; but Cambrian sand- 
stone and conglomerate adjoin Athabasca lake and also extend nearly 
200 miles west from the head of Chesterfield Inlet. 
On the treeless Barren Lands of the north, which comprise the 
greater part of the country, immense herds of caribou pasture in the 
summer, retiring southward to the woods in winter. One herd, of which 
two photographs are given, was estimated to number between one and 
two hundred thousand. 
The contour is only slightly diversified. It presents mostly a vast 
undulating plain, having an inland altitude of 1,000 to 1,500 feet, with 
rare hills a few hundred feet higher, and declining gradually eastward tu 
the shores of Hudson bay. Much of the surface is sandy or stony till, 
with only shallow and ill-defined valleys, of which the author says: 
■'Since the disappearance of the Keewatin glacier, the streams have had 
very little power of erosion, for they are frozen up most of the year, 
and each spring, as they open, the ice packs the boulders that form their 
banks into massive walls which resist erosion almo.st as effectually as the 
unbroken rock itself. Besides this, the time since the disappearance of 
the glacier may not have been very long." 
The courses of glacial striation and transportation f)f drift imply, as 
the author shows, that the ice-sheet in its departure became divided into 
several separate areas. The reviewer thinks, however; that the maxi- 
mum extensions of the confluent North American ice-.sheet were nearly 
contemporaneous from its Laurentide, Keewatin and Cordilleran centers 
of outflow. The obser\'ations of Chamberlin, Todd, and the writer of 
this review, prove that continuous marginal moraines pass from the 
Laurentide to the Keewatin ice front in Minnesota and the Dakotas, 
south of lake Agassiz and also from the east to the west sides of that 
glacial lake. 
Marginal moraines and eskers were noted by Tyrrell ni many places 
throughout the country here reported. After the ice-sheet had mostly 
disappeared, the land west of Hudson bay lay nearly 500 feet lower than 
