180 
and borings on each side of it. This is at the best merely 
an outline, but it is probably better than attempting to lay 
down the deposits over a great extent of country, without 
possessing sufficient data for a map of such changeable 
deposits as those of the drift are, it being considered more 
desirable to give an incomplete rather than a made up 
description. Certainly it is not intended to pretend to lay 
down the drift deposits over 600 square miles of country ^ 
and to predict what beds lie under. Some districts will be 
more particularly described, because materials are at hand 
for doing it. The county around Poynton, and High Lane, 
Stockport, and Brinnington, between Manchester and Old- 
ham, and Manchester and Middleton and Rochdale, near 
Bury, around Clifton, Swinton, Astley, Leigh, and Asliton- 
in-Mackerfield. In addition detached sections proved by 
boring or sinking will be given, and the height above the 
sea of the localities where it can be ascertained. 
In memoirs published in the Society’s Transactions,* the 
order of superposition of the drift beds at Manchester was 
given by me in the following descending order, namely : — 
(1) valley gravel; (2) forest sand and gravel containing 
beds of till and clay; (3) till or boulder clay; (4) lower 
gravel and sand. In a paper published by the Manchester 
Geological Society,*}' “after noticing at length the great value 
to all classes of society of a correct knowledge of those 
superficial deposits which were formerly termed diluvium 
but are now better known by the name of drift, the author 
describes the whole of the counties from the Irish Sea to 
the foot of the Pennine chain as being more or less covered 
with different portions of foreign drift so that the under- 
lying strata are only visible in steep escarpments, the great 
lines of drainage, or in artificial sections. In some places it 
l’eaches to heights of 1000 to 1200 feet above the level of 
# Vols. Till, and X. (Second Series), 
t Proceedings of the Society for 1842-3, p. 6. 
