NORTH-WEST OF ENGLAND AND NORTH WALES. 89 



specimens of the several beds, weighing about 8 lb. each, to my 

 friend Mr. David Eobertson, F.L.S., F.G.S., of Glasgow, who kindly 

 made a very full Report, which I annex in an appendix. 



It will be observed that bed No. 1 contains a few freshwater 

 Ostracoda among numerous fragments of marine shells. 



As I believe from other evidences that this is the nearest approach 

 to a littoral deposit we find in our Drift, it might well happen, if a 

 side stream had entered the Mersey at this point, that freshwater 

 Ostracoda would get mixed with marine remains. 



Xo. 2, the reddish-brown clay, consists of 60 parts of mud, 32 of 

 sand, and 8 of gravel, about one half of the sand and gravel being more 

 or less angular, the other half well rounded, and one piece finely striated. 



Wo. 3, red muddy sand, much waterworn, contained very small 

 chips of shells and a fragment of a starfish and one Poraminifer. 



rTo. 4, red clay, consists of 58 parts fine mud, 20 of sand, and 22 of 

 gravel, mostly small and waterworn. 



It is unnecessary for me to give more particulars, as they will be 

 found in Mr. Bobertson's very careful report ; but it is important to 

 notice the effect of the differing x^roportions of the three constituents, 

 viz. mud, sand, and gravel, on the nature of the clay. It will be ob- 

 served that bed No. 4, which I describe as plastic clay from which 

 bricks are made, contains 2 per cent, less sand than clay jSTo. 2 ; but 

 the sand' is replaced by a larger proportion of gravel, which does not 

 tend to make the clay "short" as sand does. The gravel is not very 

 noticeable to the eye ; but on attempting to cut the clay with a knife, 

 its presence is very soon discovered ; at the same time I was hardly 

 prepared for so large a proportion of gravel as 22 per cent. 



I have dwelt much on these sections, as it is seldom one has an 

 opportunity of examining excavations on so large a scale, and they 

 are instructive as showing how the beds of which the drift is com- 

 posed vary as new faces are exposed. 



I have given an exact and literal description of the appearance of 

 the beds, leaving for discussion afterwards whether it is possible 

 geologically to separate them. 



The New Garston Dock. — These excavations I have already de- 

 scribed in a communication to the Liverpool Geological Society *, 

 therefore it will suffice to say that the Boulder-clay here rests upon 

 a very regular shelf of rock covered with the usual red sand and 

 rubble, varying from a few inches to three feet thick. In some 

 places current-bedded sand and gravel,. and mixed clay and gravel, 

 occur between the red sand and the Boulder- clay. 



Garston is about 5 miles above Liverpool, on the same bank of the 

 Mersey. 



Wiclnes. — The deposits here are described in the paper on the 

 " Buried valley of the Mersey " already alluded to f . The deepest 



* " The Glacial and Postglacial Deposits of Garston and the surrounding 

 District, with remarks on the structure of the Boulder-clay," Proc. of the 

 Liverpool Geol. Soc, Session 1874-75. 



t Proc. of Geol. Soc. of Liverpool, Session 1872-73. 



