101 
THE GLACIAL DEPOSITS OF THE BRADFORD BASm. 
BY THOMAS TATE. 
The glacial deposits of this locaKty are interesting, as 
probably indicating the most southerly point reached by the 
North of England ice-sheet, east of the Pennine range. 
Bradford lies in a horseshoe-shaped basin five miles in 
diameter, having a northern outlet into the Aire valley at 
Shipley. The watershed ranges from 600 to 700 feet along 
the eastern and southern border, but rises to 1,200 feet on the 
western margin of the basin. The floor of this area, where 
the various streams converge, lies about 320 feet above sea- 
level, and the drainage thence is conveyed by the Bradford 
Beck to the Aire, at a point only 200 feet above the sea, the 
triie floor of the Aire valley lying more than 30 feet below 
this. 
Where the Thornton Railway passes under the Lancashire 
and Yorkshire line in Ripley Fields, recent excavations have 
exposed, at a depth of 25 feet, a bed of till 8 feet thick, the 
base not reached. (Lat. 53° 47', Altitude 400 feet^) It is 
a tough, fine-grained, unstratified blue clay, that resists the 
blast or the pick, and has to be removed by a slow and 
tedious process with the aid of a steel harpoon. This clay 
effervesces very freely upon the application of hydrochloric 
acid. Included within it, as though pitched in anyhow, lie 
numerous sub-angular or well-rounded fragments of grits, 
shales, and blue limestones, the latter polished and well 
ice- scratched. On some the striae run lengthwise, while on 
others they cross each other at all angles. Many of the 
larger angular blocks, 18 inches to 2 feet in length, are 
polished and striated only on one surface. This till closely 
resembles the till recently opened out near the Skipton 
station, and is not unlike the blue till overlaid by red 
boulder- clay of Wigan, West Houghton and Chorley, in 
