2 March, The Superficial Geology of Manchester. 



deposits when they occur at high levels ; loam and peat also come 

 under this category. These deposits are, of course, post-Glacial. 



The low-lying area of the south-west of Manchester is almost 

 entirely underlain by these deposits, which are spread on either side 

 of the River Irwell and its tributaries, the Cornbrook, Medlock and 

 Irk. 



From this area the gravels extend up the valleys as follows :— 



On the south side of the River Irwell itself, below the confluence 

 of the Cornbrook, the gravels extend as far as the Stretford Gas 

 Works, while to the south of the Cornbrook they reach a little way 

 beyond Alexandra Road. In the Chorlton district the gravels 

 stretch a little to the east of the point where Piatt Brook joins the 

 Cornbrook. 



Hulme, lying between the Cornbrook, the Medlock and the 

 Irwell, is entirely on river gravels and sands. Farther north, the 

 gravels cover the angle between the Medlock and the Irwell, and 

 reach as far as the south-west corner of Central Station, and the 

 junction of Minshull Street and Whit worth Street. Above this the 

 gravels lie only very close to the Medlock itself. 



On the north side of the Irwell, below the confluence of the 

 Medlock, the gravels underlie the area now occupied by the Ship 

 Canal docks, while on the same side of the river, below the junction 

 of the Irk, they occupy a comparatively narrow belt. 



Between the points where the Irk and Medlock join the Irwell 

 the gravels continue to Deansgate, where they gradually thin out, 

 being replaced by Boulder-clay at Central Station, at the corner of 

 South Street and Peter Street and in Albert Square. 



In the Irk valley itself river deposits occupy a narrow belt on 

 either side the stream. 



Above the junction of the Irk and Irwell, on the right side of the 

 Irwell, river gravels occur in Cheltenham Street, Pendleton and in 

 Cobden Street. 



On the left side of the river there are alluvial deposits in Sussex 

 Street, Broughton, and in Groecian Street, Broughton, while, accord- 

 ing to Binney, they occupy the whole tract encircled by the loop of 

 the Irwell. 



2. Boulder-clay. — The Boulder-clay of the Manchester district is 

 entirely of the North- Western Drift type — that is to say, the boulders 

 contained in it are mainly from the Lake district, and apparently it 

 contains none of the limestone blocks which characterise the Ribbles- 

 dale Drift. The boulders themselves are often of enormous size, as, 

 for example, the one which was obtained from Oxford Road, and is 

 now placed in the quadrangle of the University. 



The Boulder-clay covers South Manchester in areas where it is 

 not replaced or overlain by river deposits. In Salford and the south 

 of Pendleton it covers the ground except in the river valleys. In 

 Clayton and Newton Heath, Beswick and Bradford it forms the 

 only covering, and in North Manchester it occurs to the east of 

 Rochdale Road. 



3. The Glacial Sands. — The sands often attain great thickness. 



