﻿1851.] 



TRIMMER ON ERRATICS OF CHESHIRE. 



203 



surface. At the aqueduct by which the canal crosses the Dane about 

 ten feet of black shale are visible, covered by five or six feet of coarse 

 reconstructed gravel, much rolled, which has been derived from the 

 materials of the denuded Till and Upper Erratics. On the same left 

 bank of the river, about a quarter of a mile lower down the stream, 

 we have about forty feet of black shale, covered by about twelve feet 

 of reddish sand and seven feet of reconstructed erratic gravel. At 

 Colley's Mill, nearly opposite, red marl is exposed in the bed of a 

 tributary of the Dane ; and a quarter of a mile further down, on the 

 left bank; it forms a cliff about sixty feet high. 



The road from Leek to Congleton for the last mile descends, first 

 about twenty or thirty feet, over some rounded hills of sand, to a level 

 tract, covered with rolled and reconstructed erratic gravel, on which 

 Buglawton stands. There are two other descents, of twenty feet each, 

 to two similar level tracts or terraces, the lowest of which consists of 

 loam with many large pebbles, both local and erratic. Another fall 

 of twenty feet reaches an alluvial deposit of loam upon gravel, about 

 seven feet above the level of the present stream. 



At Congleton, on the right bank, is a cliff about ninety feet high, 

 the upper twenty or thirty of which consist of reddish sand with 

 granitic and other foreign small detritus. Red clay, with scratched 

 fragments (Till), is seen to rest on this sand in the brick-field about 

 halfway between the bridge at Congleton and the junction of the 

 Macclesfield and Stockport roads. From this point, we have a clay 

 subsoil between the two roads for about two miles, covered either by 

 a sandy soil, or a mixture of the sand of the Upper with the clay of 

 the Lower Erratics. 



At Cheney Gate, hillocks of the Upper Sands commence, and con- 

 tinue to Macclesfield. In descending from Cheney Gate to North- 

 rode Station the same succession of deposits is crossed — first sand, 

 then clay, down to the railway. At the Station a cutting fifteen feet 

 deep has been made in the Till, which is full of small gravel and con- 

 tains many fragments of shells. It passes down, as shown by a well 

 that was being sunk at the time of my examination, into a fine red 

 clay, with a very few pebbles and fragments of shells. Beneath this 

 clay, which is twelve feet thick, is reddish sand, which one of the 

 railway workmen informed me they had penetrated to the depth of 

 ten feet without reaching the bottom. 



Similar pure red clay, beneath red gravelly clay, occurs in the brick- 

 field at Fodenbank near Macclesfield, where the base of it is not ex- 

 posed. I have found no shells in this Lower Sand. Sir P. Egerton 

 has described* a bed of pebbly sand, at least thirty-six feet deep, at 

 "the Willington" near Tarporley, Cheshire, about twenty-five miles 

 west of Macclesfield, containing marine shells. It was " separated, 

 by a well-defined line, from an overlying deposit, twenty feet thick, 

 of the ordinary diluvium of Cheshire, containing pebbles and boulders 

 of granite, slate, greenstone, and other rocks." This diluvium con- 

 sisted chiefly of sand. From the low level, seventy feet above the 

 Mersey, it is probably reconstructed. If the shelly gravel of Wil- 

 * Proc. Geol. Soc. vol. ii. p. 189. 



p 2 



