valley.

At Fen Bogs, where there is a great depth of peat, Professor Kendall has discovered that if it were cleared out, "the channel through the watershed would appear as a clean cut, 75 feet deep." The results of the gouging operations of this glacier stream are further in evidence where the valley enters the Vale of Pickering, for at that point a great delta was formed. This fan-shaped accumulation of bouldery gravel is marked in the geological survey maps as covering a space of about two square miles south of Pickering, but the deposit is probably much larger, for Dr. Thornton Comber states that the gravel extends all the way to Riseborough and is found about 6 feet below the surface, everywhere digging has taken place in that direction. The delta is partly composed of rounded stones about 2 feet in diameter. These generally belong to the hard gritstone of the moors through which Newton Dale has been carved. Dr. Comber also mentioned the discovery of a whinstone from the great Cleveland Dyke, composed of basaltic rock, that traverses the hills near Egton and Sleights Moor, two miles above the intake of Newton Dale at Fen Bogs.

The existence of this gravel as far towards the west as Riseborough, suggests that the delta is really of much greater magnitude than that indicated in the survey map. It has also been proved that Newton Dale ceased its functions as a lake overflow, through the retreat of the ice-sheet above Eskdale long before the Glacial Period terminated, and this would suggest an explanation for the layer of Warp (an alluvial deposit of turbid lake waters) which partially covers the delta. The fierce torrents that poured into Lake Pickering down the steep gradient of this canon would require an exit of equal proportions, and it seems reasonable to suppose that the gorge at Kirkham Abbey was chiefly worn at the same time as Newton Dale.

Another delta was formed by the upper course of the Derwent to which I have already alluded. In this instance, the water flowed along the edge of the ice and cut out a shelf on the hill slopes near Hutton Buscel, and the detritus was carried to the front of the glacier. This deposit terminates in a crescent-shape and now forms the slightly elevated ground upon which Wykeham Abbey stands. The Norse word Wyke or Vik means a creek or bay, and the fact that such a name was given to this spot would suggest that the Vale was more than marshy in Danish times, and perhaps it even contained enough water to float shallow draught boats. Flotmanby is another suggestive name occurring at the eastern corner of the lake about four miles from Filey. In modern Danish flotman means a waterman or ferryman, and as there is, and was then, no river near Flotmanby, there is ground for believing that the Danes who settled at this spot found it necessary to ferry across the corner of the lake. Before the Glacial Period, the Vale of Pickering was beyond doubt from 100-150 feet deeper at the seaward end than at the present time, and even as far up the Valley as Malton the rock floor beneath the deposit of Kimeridge clay is below the level of the sea.

CHAPTER IV

The Early Inhabitants of the Forest and Vale of Pickering