io6 11 ic American Geologist. February, i89» 
Taylor and others seems to be the highest l)each of lake Al- 
gonquin. 
Nipissing Great Lakes. The highest beach of this post- 
glacial lake, called the Nipissing beach by Taylor, forms a 
conspicuous feature near the level of lake Superior from 
Beaver Bay to Port Arthur. The conclusions drawn by Tay- 
lor with respect to this beach are satisfactory. The beach 
is 6 1 feet above lake Superior at Port Arthur and is readily 
recognized at lower levels, at Wauswaugoning Bay, Grand 
Portage, Grand Marais, Cascade river, three miles east of the 
Temperance river at Tofte postofifice, and one-half a mile west 
of the Baptism, river. West of the last-named locality the 
beach has been obliterated by recent wave action, and proba- 
bly passes below the level of lake Superior near Beaver Bay. 
Taylor places its distance below the lake at Duluth at 25 feet. 
This gives a rise of 86 feet toward the northeast, between Du- 
luth and Port Arthur. 
Lake Gabbro. North of the ]\Iesabi moraine and east of 
Gabbro lake, a glacial lake having an area of one hundred 
square miles at its maximum extent, existed for some time 
after the recession of the ice from the moraine. The shores 
of the lake were formed by the Mesabi moraine on the south, 
a high rock ridge on the west, the ice barrier on the north 
and the highlands on the southeast. This region forms a 
basin, sloping toward the northwest, which is covered more 
or less with stratified sand and fine clay. Beaches have not 
been identified. The short duration of the lake and the 
character of the region in which it existed did not present 
favorable conditions for the formation of prominent beaches. 
The outlet was south to the Stony river. The lake was named 
lake Gabbro on account of its central location in the gabbro 
area of northeastern Minnesota. 
Glacial Rivers. The courses of the glacial water are 
quite conspicuous in many places. The valleys of the Clo- 
quet, Saint Louis and Embarras rivers show that these rivers 
at one time were much larger. The extensive stratified de- 
posits in these valleys indicate a drainage from the northeast. 
At the headwaters of these rivers abandoned channels across 
the present water divide show that their sources were further 
north and east. The channel across the central part of T. 59 
