1872.J DAKTNS TOEKSHIRE GLACIAL PHEIS^OMEXA. 385 



scratched does the drift raaterial become. This is again an argu- 

 ment in favour of the glacier origin of the drift. 



There is another point to which I Avish to direct the attention of 

 geologists, that we may learn whether there is any thing in it or 

 whether it is merely a local accident. I was very much struck 

 with it when, three or four years ago, I first became acquainted with 

 the great drift-area. It is this : the drift is very often found 

 entirely on one side only of a valley, and that always the same side 

 with reference to the source and origin of the drift, viz, on the lee 

 side of hills, as drifted snow or any other drifted material. I will 

 give some examples. The drift of the Aire basin doubtless came 

 from the north and north-west. Now the south side of the Aire 

 valley near Keighley is comparatively free from drift, while the 

 north side is thickly covered with it. Again, take the Worth 

 valley, which runs to the N.E.; the east side is free from drift, 

 while the west or lee side is thickly covered. The same appeared to 

 me to be the case with Wharfedale where it runs east and west, 

 viz. that the north side was thickly covered, while the south was 

 free. If it should turn out that this is any thing more than a local 

 accident, it points to a universal ice-sheet and to the drift being 

 moraine profonde deposited thickly on the lee side of hills while the 

 ice-sheet j^assed over it, dropping it in its course, whereas on the 

 exposed side the ice, as it ascended the slope, swept eveiy thing before 

 it. Of course, such valleys as lay in the direction of the ice-flow 

 will not have this contrast of sides. 



Besides the scratched gravels, we have also in certain places 

 mounds of water -worn gravels arranged in confused heaps, often 

 enclosing hollows, known by the name of Karnes or Eskers. These 

 kames bear a distinct relation to the valley ; they occur at certain 

 parts only of the valley, and were evidently deposited in the bottom 

 of it ; they form irregular mounds, sometimes quite blocking up the 

 valley ; they consist of stones that have been once scratched, bxit 

 whose scratches have been worn off, doubtless by the action of the 

 water in which the kames were deposited ; so that the kames are 

 either rearranged drift, or consist of driit deposited in the sea (for 

 lakes are here out of the question) and which got its scratches 

 effaced in the process of deposition. That the pebbles were once 

 scratched is shown by the faint traces of scratches that sometimes 

 occur. 



From the way in which kames pass gradually into scratched 

 gravels, and from the definite position they occupy in the valley, it 

 seems to me probable that in many cases kames are merely the 

 result of moraines deposited in the sea instead of on land. 



It seems to me that the long straight ridges that run across hills 

 without any reference to contours, and which are also called kames, 

 are something quite distinct from the irregular valley-mounds just 

 described. 



That these valley kames are due to sea-action is also shown by the 

 fact that the cross-bedding of the sand dips up the valley as well as 

 down it. This implies a current setting up the valley. When the 



