pO) SCIENTIFIC SURVEY OF TURNER’S LAKE 
SUMMARY 
The Isle-au-Haut lake is clearly not the remnant of a fiord. It 
has no residual inflow nor any indication of prior river erosion. 
The drainage that keeps it in existence is small and highly 
obstructed; hence, in some degree no doubt, the lack of a normal 
circulation of the waters makes them somewhat stagnant and over- 
loaded with organic matter. It is probable that this excess of 
organic matter has made conditions of living unwholesome to many 
lacustrine forms of life usual to the lake waters of eastern America. 
These suggestions, however, still leave many things to be explained, 
for adaptation is clearly evident in the case of the introduced fish, 
the salmon, and would hence seem to have been possible for other 
normal lacustrine species here absent. The boundary of the lake 
at the south is so obviously barricaded by a rock wall, that one can 
not ascribe the making of the lake valley to sea action; that is, it 
seems to have no relation, in origin, to the “goes” elsewhere 
described as caused by the removal of a joint-bounded rock prism. 
The tangible explanation of the origin of the lake basin seems now 
to rest upon the conception of a down-sunken fault bluff of the 
rocks, bounded and controlled by major fault lines parallel to the 
axial rock structure of the Island. 
UN, (Os 
