( 'orrespondence. 897 
CORRESPONDENCE. 
The Algonquin and Nipisstng Beaches. In your editorial com- 
ments on my letter of February 15 last, published in the American Ge- 
ologist for April, I am somewhat surprised to find another repetition 
of an error wbieh is more than palpable and which has been several 
times corrected in the clearest terms. Towards the close Mr. Upham 
uses these, words, " * * there ensued lake Algonquin, represented by 
the Algonquin or Nipissing beach, * * ' Why docs lie say Algonquin 
or Nipissing? In saveral previous papers Mi-. Upham has made the same 
statement, viz.: that the Nipissing beach is the same as the Algonquin, 
and I have almost as many times pointed out the error of such a suppo- 
sition. It seems to me that the time has come when the truth should 
be made clear. The Algonquin and Nipissing beaches are, in fact, ab- 
solutely distinct and separate throughout the whole-area of their extent. 
The Algonquin beach always occurs at a higher level than the Nipis- 
sing. The former was probably made by a glacial lake held in by an ice 
barrier in the Ottawa valley; the latter was certainly not glacial and 
never had any connection or relation to any glacier whatever. The two 
beaches are not at all alike in their physical characteristics, nor in the 
strength of their development. Their planes are not parallel. Their 
attitudes are not similar except in the fact that they both ris i towards 
the northeast. Their declivities are different and their minor deforma- 
tions are not coincident either in area or amount. They represent two 
entirely separate stages of lake history and they record two different 
epochs of continental deformation. The supposition that they are one 
is entirely erroneous and inevitably vitiates our conception, not only of 
the lake history, but of the Pleistocene history of the northeastern 
quarter of the continent. My connection with the study of these two 
beaches may be briefly summarized as follows: 
Random observations on the Nipissing beach began in the summer of 
1890, but the recognition of its real significance and the naming of it 
did not occur until the autumn of 1893. Systematic tracing began and 
was well advanced that season. From all the observations made up to 
that time it was found that the beach wra« clearly identified for long 
continuous distances on the pouth shore of lake Superior; on both sides 
of the .north end of lake Michigan: across the northwepl end of lake 
Huron: at Sault Stc Marie, Mackinac strait and at the Nipissing pass 
at North Bay, Ontario. It was doubtfully identified also at several 
other widely separated places. 
In 1895 a large number of new observations were made, greatlj ex 
tending the area of the identified beach. 1 1 was clearly made out along 
the north side of lake Superior from Porl Arthur to Peninsula harbor 
and eastward from Sault Stc. Marie to Nairn, about half way to North 
bay. It was traced almost continuously southeastward from Mackinac 
to a point a few miles south of llarrisvillc when, it passes under lake 
