Vol. 58. GLACIER-LAKES IN THE CLEVELAND HILLS, 599 
Each of these valleys, when it reaches the gravel-bench, undergoes 
a sharp westerly deflection; moreover, across the flat top of the 
gravel-bench, a series of deep channels has been left, forming an 
almost complete series of links connecting each stream or valley with 
its neighbour on the west. These channels are generally at a level 
of 30 or 40 feet above the streams that they appear to have served, 
and only in two cases, Beedale Beck and Sawdon Beck, are they at 
present occupied by streams. One very fine example, forming 
Rushton-Cottage Pasture, the deepest of the whole series, is inter- 
rupted by a ridge of gravel which shuts in a deep hollow in a part 
of the channel. 
At the western end, by Wykeham and Rushton, the gravel-terrace 
is extremely uneven, and it comes to an abrupt and singular 
termination in a great horn running for nearly a mile out into the 
valley, from ‘the dead-flat floor of which it rises as a bold and 
picturesque ridge bearing the ancient Wykeham Abbey. This portion 
of the gravel-mass presents contours quite unlike the scarp of the 
terrace at West Ayton or Hutton Bushel. A small outlier of gravel 
lies to the west of the Wykeham ridge, and rests upon a prominence 
of rock forming Gallows Hill. Beyond this, both terrace and gravel 
abruptly cease. 
Some features of the composition and condition of the gravel may 
be mentioned. Many sections exist, from which its constituents 
can be ascertained: I paid particular attention to two gravel-pits 
at Yedmandale and Hutton Bushel. At the former the beds 
were of sands and gravels, the pebbles consisting mainly of 
Jurassic sandstones and limestones, with many Cheviot andesites, 
some greywackes (probably from the Valley of the Tweed), some 
jasper, and a few granite-pebbles. I also found fragments of 
marine shells, among which I identified Tellina balthica and 
Cuprina islandica. At Hutton Bushel, in a grayel-pit on the 
200-foot contour, rather coarse, horizontally-bedded gravels were 
exposed, often of the type (so common in Glacial accumulations) 
which I have termed dry gravels, that is stones packed with 
open interspaces not occupied by sand or other infilling. ‘The 
stones were mainly local (Corallian), but there were fragments of 
Kimeridge Clay, many pebbles of Cheviot porphyrite, and some 
Magnesian Limestone of the Roker (Sunderland) type, gneiss, and 
granite. I was informed by the Rev. W. C. Hey that shell- 
fragments are common in these gravels, and that a great many were 
obtained in a temporary pit opened immediately east of Forge Valley 
near Kast Ayton. 
We have here, I think, a body of facts which show conclusively 
that the Hutton-Bushel terrace is not a simple lake-beach. The 
pronounced fall of its surface from east to west might, of course, be 
explained upon the supposition of a differentia] movement or tilt of 
the region; but, even if there were no other difficulties remaining, 
I should hesitate to have recourse to so bold an expedient, except 
in presence of proof of such a movement of an overwhelming 
character. There are other, and in my opinion even more weighty, 
