302 PROCEEDINGS COTTESWOLD CLUB 1912 



Water. — Dealt with in Appendix. 



Commercial Uses. — In times past, the clay has been ex- 

 tensively dug for brickmaking, as at Folly Lane, Harp Hill and 

 other places ; but at the present time the extensive Battledown 

 Brick Works are the only ones open. By itself the clay 

 here is too strong to make good bricks, so yellow sand is ground 

 up with it to make a suitable loam. 



In brief, the process of brickmaking at these Works is as 

 follows : ' 



After the clay has been dug (Plate xxxiv., figs, i and 2) it is 

 loaded on to trucks which are taken to the top-storey of a four-storied 

 building. Here it is tipped into a large hopper. Giant steel teeth 

 chew it up and pass it through rollers, situated on the third floor, 

 which still further reduce the size of the lumps of clay. After passing 

 through two pairs of smooth rollers on the second storey the clay goes 

 into the " mixer," where it is stirred with water by means of revolving 

 beaters. From the mixer it passes through a final pair of rollers set 

 " iron and iron " and thence into the " pug," where it is compressed 

 and pushed through a mouth-piece (the size of a brick) on to the cutting- 

 table." A frame-work on this table cuts off ten bricks every ten seconds 

 or 36,000 per day. 



The green bricks are next dried, either in the American Dryer 

 (fig. 4) or, in summer time, in open-air hacks. When sufficiently dried, 

 by either means, the bricks are placed either in the large German Kiln 

 or in the smaller Round Kilns. The German Kiln at these Works 

 holds over a quarter-of-a-million bricks. The fire never goes out, but 

 travels, year after year, round and round the long oval-shaped tunnel, 

 being fed by the coal poured into it through the little holes at the top. 

 Far away at the rear of the retreating fire the bricks are cool enough 

 to be taken away. Far away in front of the advancing fire the dried 

 bricks are being continually set for it to burn in its round. 



Gravel. — Gravel, formed of waterworn pieces of limestone 

 derived from the bands and nodules in the Upper Lias, but 

 principally from the Inferior Oolite, is often found to underlie 

 the yellow sand. The superposition of sand on gravel was very 

 clearly seen in an excavation for a sewer in the Tivoli district 

 (60) of Cheltenham. 



The portion of the gravel exposed in the railway-cutting 

 at Chestnut Farm was certainly once overlaid by sand. That 

 this was so is obvious from the fact that sand-grains occur 

 with the gravel. The gravel over the greater part of this 

 outlier, however, is free from sand and so is that composing the 

 Hunting-Butts and Starvehall-Farm outliers. The former 



I This account is derived from Messrs Webb Bros.' booklet " Brickmaking without Straw." 

 A full description of the Works will be found in Proc. Cheltenham Nat. Sci. Soc., vol. i., pt. 4 (1910), 

 pp. 264-269. 



