The highest springs of the Cuyahoga drainage basin are in northeastern Geauga county, in northeastern Ohio, about fifteen miles south of the shore of lake Erie. Thence the Cuyahoga river flows first about forty miles southwestward to its great bend close north of Akron, there turning to a general course slightly west of north which it holds through its lower thirty miles, entering lake Erie after passing through the central part of the city of Cleveland. This paper considers chiefly the last four miles of the Cuyahoga valley which are comprised within the limits of Cleveland. The level of the river in its stage of low water along this distance, from the junction of Big creek to its mouth, is the same as lake Erie, or differs only by a descent of 1 or 2 feet. Along all the south-to-north part of . . .