Abandoned Beaches of Lake Superior. — Tan I or. 127 
is needed to establish the connection. At Root rivei- near 
Sault Ste. Marie Lawson's highest beach is the Algonquin, 414 
feet above lake Superior. Between this place and the Jackfish 
group it seems hardly conceivable that there could have been 
a glacial or any other kind of barrier, and hence the inference 
seems clear that the upper beach of Jackfish grou]) is tlie Al- 
gonquin. But thei'p remains some uncertainty, of the identi- 
ty of tliis beach in the west end of the Superior basin. 
No attempt is made here to correlate the fragmcntai-y inter- 
mediate beaches, those at horizons between the Algonquin and 
Nipissing. The last named beach, however, was clearlj' rec- 
ognized at every place where tlie lower coast was examined. 
It is about 60 feet above the lake at Mt. McKay and Port Ar- 
thur, 90 feet at Nipigon station, JOS or 110 at Jackfish and 
two miles east of tliere and 110 to 115 at Peninsula Harbor. 
Its great length, compounded of many beach ridges forming 
beach-plains, gives it a pliysiographic prominence that is not 
equalled by any other shore line of the lake region.* 
Several rather light but distinct beaches were found below the 
Nipissing, especially in the extreme north where theNipissing 
beach is highest. The probable existence of at least one such 
beacli was inferred from the observations of 1893 on the south 
Superior shore, and it was called the Sault beach because it 
appeared to hinge on the outlet at Sault Ste. Marie. On the 
south shore it is now all submerged and appears to lie about 
50 feet below the Nipissing beach. It was estimated that it 
would be found somewhat more than 50 feet below the Nipis- 
sing along the north shore. The beach 28 feet above the lake at 
Nipigon, 33 feet at Jackfish and 40 to 45 feet at Peninsula 
seems to meet this expectation. The fragments so far found, 
however, are too few to warrant more than a prf)visional cor- 
relation. 
Until the attainment of the results here presented the hy- 
pothesis entertained with most favor in explanation of the 
high shore lines of the Superior basin was that tliey were of 
marine origin. It was expected that the Algonquin beach 
would 'be found at a higher level than has. been observed on 
the north shore and that there were straits northward to Hud- 
son bay through the passes at Kenogami lake near Jackfish 
*Am. Geol., Vol. XV, March 1895, pp. 1(35-167; May, 1895, p. 312. 
