Geology and Natural History. 313 
Mr. Harrington’s report on the rocks and minerals is an import- 
ant one. It contains analyses of oligoclase, hornblende, m magnet- 
ites, hematites, limonites and — species, ’ besides observati ons 
on the associations of the specie 
say concerning ee tant Physical Features "eehibited 
in we Valley of the Minnesota River and upon their signification ; 
by Sh orp sii , Major of Engineers and Bvt. Maj. A U. 
8. A. ., with several maps. Engineer Dept., my. 
Siac or We rren ete s attention, in this Report, to the width. and 
extent of the valley of Minnesota River (one of the head tributaries 
of the Mississippi) a feature continued even to its source in Lake 
Traverse, and to the great disproportion between its size and that 
of the stream'now oc cupying it. Henext —- facts, derived from 
Prof. H. Y. Hind and other observers, respecting t the great extent 
of the level region and stratified dri ift de eposits about Lake Win- 
Traverse. The conclusion deduced is that in the Glacial era the 
land to the north about Lake Winnipeg was more elevated than 
now, so that the drainage trom that lake was es oo south, instead of, 
as now, through Nelson’s River, to Hudson Bay ; and that Lake 
ancient bed west of Pembina, as given by Mr. Owen, is 210 feet; 
that the lake bed there is about 50 feet above Red River, and this 
river at this point is about 100 feet above Lake Winnipeg; and 
hence he adds, “this lake terrace is 360 feet above the level of 
hi at is par excellence the ancient beach in the ails of Lake 
Winni Dr. Owen thus ie it as it presents itself a few 
miles south of the 49th parallel.” 
en the southward slope of the surface came to its end 
through a northern subsidence, Nelson’s River became the outlet 
—a narrow gorge abounding in water-falls. J. D. D. 
4, An examination of the Theories that have been proposed to 
Fo Jor the Climate of the Glacial Period ; by Tuomas a 
On, uart. 
decision of astronomers is against it, but he holds that “ until 
astronomers have Senonaidaied this question with the light of our 
