284 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 1, 



matter. In speculating on the general absence of diluvium, the 

 author alludes to the probability of its being concealed by the exten- 

 sive tract of alluvium, and mentions rolled gravel, containing frag- 

 ments of all the neighbouring rocks, from the old red sandstone to 

 the chalk, as occurring at the mouth of the Avon, associated with the 

 bones of quadrupeds peculiar to the diluvial beds, and covered by 

 peat. He speaks also of ridges of sand and shingle, provincially 

 called " batches" rising through the alluvial deposits in several 

 places, instancing as one of the most remarkable that on which the 

 village of Yatton stands. 



While recently engaged in constructing a map of the soils, sub- 

 soils, and substrata of Sir Charles Elton's estate, in the parish of 

 Clevedon, I saw this gravel in the railway-cutting near the Yatton 

 Station, but had no opportunity of examining the materials of which 

 it is composed. 



In the course of my survey of that estate, I was struck with two 

 remarkable facts. The first was the general absence of erratic de- 

 tritus ; the second, a general uniformity in the composition of the 

 soil, whether on the Carboniferous Limestone, the Coal-measures, or 

 the Magnesian Conglomerate ; a uniformity which seemed to indicate 

 a blending, by aqueous operations, of the fine detrital matter of more 

 than one formation, rather than the exclusive derivation of the soil 

 from the rock on which it rests. 



Of coarse extraneous matter it was long before I discovered any 

 fragments large enough to be called pebbles, with the exception of a 

 few rolled fragments of quartz and of limestone, at heights of about 

 100 feet above the sea. 



In the alluvial clay, generally free from pebbles, I also found a few 

 chalk -flints near the southern boundary of the parish, where it ap- 

 proaches the 'batch' or shingle-bed of Yatton. The bed of the 

 stream called the Blind Yeo was described to me, by a labourer who 

 had frequently scoured it, as containing many such pebbles. With 

 respect to the soils, I found in them a great tendency to redness 

 at all elevations, and on every rock. This colour, which appears to 

 have been derived by means of the washing of water from some of 

 the adjoining red formations, may be ascribed at low levels to the 

 New lied, — at high levels to the red beds of the Coal-measure sand- 

 stones, or to the Old Red Sandstone of the parallel and neighbouring 

 ridge of Walton Down. In either case it would indicate extensive 

 aqueous operations. 



The discovery of the remains of a bed of gravel on the summit of 

 Clevedon Down (see fig. in the Postscript), at an elevation of about 

 300 feet above the sea, confirms these views, and throws much light 

 on the derivation of the soils from other formations than those on 

 which they rest. This gravel-bed is situated at the point where the 

 lane through Norton Wood emerges upon the Down. Covering only 

 a few square yards of surface, and not exceeding three feet in depth, 

 it owes its preservation to the fact of its having been cemented by 

 calcareous matter into a tufaceous conglomerate. Its materials are 

 chiefly rolled pebbles from the difi'erent beds of Carboniferous Lime- 



