426 MK. BERXARD SMITH ON THE [Sept. I912, 



upon a cliff of rotten granite. On the opposite side of the main 

 Talley, 3 to 4 feet of red and yellow stratified granite-sand, with 

 a south- easterly dip and embedded boulders, was exposed in the 

 road-bank facing Skellerah House. The valley is 40 to 50 feet 

 deep at Corney Mill, where 15 feet of boulder-beds and stratified 

 sand rest upon more than 20 feet of exposed granite. 



At Corney Hall, a low col gives access on the west to a transverse 

 valley, about a fifth of a mile long, which is of a similar nature ta 

 that near Gillfoot and will be dealt with later on (pp. 426-28). 

 About 100 yards south of Corney Hall there is a drop in the floor of 

 the main channel, the depth of which increases to 100 feet, and its 

 drift-capped sides become steeper. At Black Dub the floor crosses the 

 200-foot contour and turns abruptly westwards, round Seaton-Hall 

 Wood, leaving the outcrop of the granite. South of this point the 

 eastern granite-wall of the old channel, as far as Kinraont Beck, 

 is still in existence ; but the western wall is wanting, and was- 

 evidently formed of ice. 



The complete channel is nearly 2 miles long, and its floor 

 falls about 75 feet per mile. 



(d) The Near-Bank 'in-and-out' Channel. — A third channel 

 as long as, or longer than, the last, lies still farther west, its- 

 general course coinciding with the western outcrop of the granite 

 which descends quickly from 300 to below 200 feet. The ice 

 apparently rested for a considerable time against this slope, and 

 steepened it by holding flowing water against it. At Near Bank, 

 owing to the crowding of the ice, the water was forced to cross^ 

 a spur of granite, and cut a splendid example of an ' in-and-out ' 

 valley about a quarter of a mile long. Its floor is 50 yards wide, 

 and lies below the 200-foot contour ; while its eastern wall is over 

 60 feet in height. A small stream dropping into the valley from 

 this side throws across the floor a low delta, upon which the> 

 stream turns and takes a southerly course (PI. XLII, fig. 2). 



(e) The Gillfoot and Corney-Hall transverse channels. — 

 The valley which introduces the Annas into the Corney Valley is 

 rather steep-sided, and some 300 yards long. In this distance its 

 floor falls about 50 feet, its almost abrupt descent being at the 

 western end, where it drops into the Corney Yalley. It connects 

 the Kinmoiit Channel, the floor of which lies at from 360 to 370 

 feet above O.D. (the Eiver Annas is at about 350 feet), with that 

 of Corney, a little below 300 feet. 



At Corney Hall there is a similar (but dry) valley, a quarter of a 

 mile long, connecting the Corney with the Near-Bank Channel. At 

 its head, immediately west of Corney Hall, is alow col, from which 

 the floor of the cross-cut descends over 60 feet in a westerly 

 direction. At its best the valley is quite 80 feet deep. Stratified 

 sand and gravel occur in the wood on the southern slope at a 

 rather low level, perhaps deposited in a small pre-Glacial stream- 

 hoUow (PI. XLII, fig. 1). 



I 



