56 PROCEEDINGS COTTESWOLD CLUB 1910 



at about a quarter of the way across it, the sand is very pure 

 and yellow (6 feet) and rests upon very dark blue Lower-Lias 

 clay. The sand is continuous across the field, and has a little 

 well-rolled, small-sized Jurassic gravel mixed with it. A similar 

 deposit was proved where the sewer runs alongside the Sand- 

 field Road; but where it leaves that road (12), blue Lias clay 

 occurs very near to the surface. The sand-bed, however, 

 is soon entered again (13), and, as far as the number 14 on the 

 map (text- fig. i), is beautiful pure sand, with but Httle gravel 

 mixed with it. At 14, however, the surface of the sand-bed 

 was seen to decline (in the section) under an increasing thick- 

 ness of yellow, blue-blotched clay with calcareous layers — a 

 deposit of the brook near at hand. At the brook the sand-bed 

 rises up again, so that on the left bank a few feet only of 

 re-deposited clay occurred on top of the sand, and on the right 

 bank none. From the bed of the Chelt some very dark-blue, 

 clayey humus was dug out. It is useful to know the relations 

 of the yellow blue-botched clay to the sand-bed, and it 

 is obvious that the sand-bed has had a broad shallow hollow 

 excavated out of it by the Chelt, and this hollow has been 

 filled up by alluvial material — in the present case, mainly this 

 pale-coloured clay. 



