8 March, The Superficial Geology of Manchester. 



of bore-holes and shafts which have been made since Hull's day, 

 together with the absence of sands in sections in the districts 

 immediately surrounding the main sand area, points to the con- 

 clusion that the sands and clays of the Manchester district replace 

 one another irregularly and do not present any definite sequence. 



Unfortunately for the tri-partite classification of the Drift, those 

 areas which have a thick top clay are without thick sands, while 

 those which have true " middle sands " have no top clay. These 

 sands, when they do occur, may overlie a clay-bed, as at the Heaton 

 Park bore-hole, or they may come straight down on to the solid, as 

 at Agecroft Bridge, Levinstein's Dye Works and Middleton Junction. 

 The Glacial sands of this district cannot be said, therefore, to form a 

 central layer between two clays. 



Distribution of the " Upper " and " Lower " Boulder-clays 



If it be accepted that the sands of Kersall Moor and Prestwich 

 are nothing more than a huge lenticular patch, it follows of necessity 

 that the clay-beds above and below these sands must be also local 

 in character. Evidence of this can be obtained from sections and in 

 the field. 



Clay underlying the sands, which would be " Lower Boulder- 

 clay," according to Hull's classification, is seen at the Heaton Park 

 bore-hole, where it is 34 feet thick, and in the well section of the 

 Crumpsall Old Workhouse, where it is 68 feet thick. These clays do 

 not form a continuous basal layer, for they are absent at Middleton 

 Junction in the north, at Messrs. Levinstein's works between the 

 Crumpsall Old Workhouse and Heaton Park, and in the Rochdale 

 Road sewer to the south, and on the west in the Irwell valley opposite 

 to Agecroft Bridge, where the sands can be seen coming down on to 

 solid rock. 



The " Upper Boulder-clay " should, according to Hull, be 

 present at Hyde, Denton, Failsworth, Oldham, the higher parts of 

 Harpurhey and Blackley, Clifton, Kearsley and Little Lever. 



From the sections given in the Hyde and Ashton-under-Lyne 

 districts it will be seen that thick sands are absent at Hyde, Hyde 

 Lane and Lordsfield, and that at Ashton Moss, where the sands are 

 thick, the top covering of clay is only 12 J feet thick. In the sections 

 given round Failsworth the sands are absent, as they are in Hollin- 

 wood, on the outskirts of Oldham. There are no sections giving 

 details of the Drift in Clifton, but at Middleton there is no top clay. 

 In the west, sections showing thick sands as at Stand Lane and Out- 

 wood have no overlying clay, and the Whitefield and Leigh pits 

 have no sand. In the typical sand area, sections at Heaton Park, 

 Crumpsall Old Workhouse and Messrs. Levinstein's works give no 

 top clay, and it is also absent both in one at Prestwich Asylum, which 

 passed through 99 feet of sand and clay without reaching rock, and 

 in the shaft at Hugh o' th' Wood Colliery in Prestwich Clough. 



In addition to these sections the top of the sands can be seen in 

 Boggart Hole Clough, above Blackley, across Kersall Moor, at Alms 



