VOL. XVII. (3) MAP OF CHELTENHAM 305 



stratified gravel associated with it. This gravel is formed of 

 well-rolled fragments of Upper-Lias and Inferior-Oolite lime- 

 stones. Some idea of the appearance of this sand-gravel 

 deposit will be obtained from the photograph reproduced in 

 Plate XXXV., fig. 2. 



The sand has not been derived from local sources, but has 

 come from a distance. 



A sample taken from the sand-deposit exposed in the sand- 

 hole at the Battledown Brick-Works, was submitted to Mr 

 H. H. Thomas, M.A., B.Sc, Sec. G.S., who reports :— 



" The sand is fairly uniform in grain, non-calcareous, and consists 

 chiefly of sub-rounded quartz with a subordinate amount of orthoclase. 

 The heavy residue is small, but interesting ; it consists of pink garnet, 

 staurolite, and well-rounded tourmaline, and a few grains of the usual 

 minerals of sedimentary rocks which have no value for the purpose of 

 tracking a sand to its source. 



" The relative abundance of staurolite in the heavy residue would 

 certainly lead me to infer that the Trias had furnished most of the 

 material, and this supposition is strengthened by the absence of many 

 characteristic minerals which are common in rocks of the Cretaceous, 

 Tertiary and western Glacial drifts. 



" I have not examined any of the Jurassic rocks of the West of 

 England, so the above remarks must not be taken too literally. 



" Another point in favour of the Trias, as I know it is that all the 

 Red Rocks of the Somerset region contain abundant pink garnet and 

 rounded tourmaline ; this evidence, however, is not so good as that 

 supplied by the staurolite." 



The following details have been obtained concerning the 

 sand-deposit : — 



26. Here numerous small pebbles of Lias and Oolite limestones are 



associated with the sand. 



27. Clean yellow sand is often dug in these gardens. 



28. The pit in work here belongs to Messrs Webb Bros., and sand is 



sold at 1/3 a load. 



29. Trenches for drains in the Waterloo-Street district proved at least 



14 feet of sand. 



30. The sand here is only i^ feet thick. 



31-32. The section of the Wyman's-Brook Sewer between these num- 

 bers is in sand at least 14 feet thick. 



33. Formerly there was a sand-pit here. 



34. Formerly there was a clay-pit here, but in the stoke-hole for a 



greenhouse 4 feet of sand and gravel was exposed above the 

 Lias clay. 



35. This district has been recently extensively built over and the 



inequalities alongside the brook have been filled up. It is one 

 in which the gravel appears from beneath the sand on a clay 

 bank and there is the consequent washing down and co-mingling 

 of deposits. Between the positions of the number (35) on the 

 map and the road, excavations showed a few feet of sand (which 

 rapidly thickens to the north) separated by a foot or two of 

 gravel from deep blue-Lias clay. 



