KENDALL : THE GLACIER LAKES OF CLEVELAND. 
13 
rising to upwards of 1,000 feet except at one point, where a 
gap occurs in a stony ridge on the western side of the valley. 
Here a narrow, sharply-cut notch breaks through the l.OUO-foot 
contour, and forms the intake of a deep channel, Holy Well 
Gill, which has all the characteristics of a lake-overflow. When 
this overflow was in operation the valley must liave been choked 
with ice and the lake formed by the drainage of the ice-sheet 
small. A little to the west at the same period a small lakelet 
must have been formed in a minor recess above Scartli Wood, 
the overflow from which cut a well-marked notch through the 
watershed into the valley leading down to Osmotherley. but 
this was of short duration, a sUght recession of the ice opening 
a lower gap, the fault-valley of Scartli Nick, which then carried 
off the waters of this and Scugdale Lake which had become 
united to it. 
Scarth Nick is a fine example of an overflow ; the valley is 
100 feet deep, with a breadth of only about 150 yards at the top 
of the cutting, narrowing to about 30 yards, or less, at the bottom. 
The floor is flat, and contains much peat. Near its confluence 
with Crabdale. a valley of normal shajie. there is an immense 
accumulation of gravel standing as a mound in the middle of the 
valley. Lake Scugdale was, at its maximum, about 400 feet 
deep. When Scarth Nick was opened, the level fell nearly 
200 feet, but the area of the lake was not greatly affected, for 
the hillslopes are steep, and the recession of the ice-front would 
compensate for the loss. 
Inglehy Grecnhoiv Lake. — The re-entrant angle of the Cleve- 
land escarpment at the eastern end is breaclied by a splendid 
overflow-channel (Plate XIV.). It is a deep, square-cut notch, 
carrying no stream now, and is a simple example of a direct 
overflow. It probably drained a considerable part of the 
ice-margin for a long period by way of Bilsdale and Ryedale into 
Lake Pickering. This overflow was recognised by tlie Rev. John 
Hawell before my survey had extended so far westward. 
Kildale Lake. — The western outlet of Kildale is obstructed 
by a moraine which rises 100 feet above the floor of the valley. 
The upper part of the valley is largely occupied with drift deposits, 
consisting mainly of sand and gravel, which cover its central 
