Journal of Proceedings. xv 



and Eeading beds obtained north of the Thames had been found tliere. 

 He thought the Chib might do good service to geology by carefully 

 investigating the strata referred to at Stifford. 



At the conclusion of Professor Morris's remarks Mr. J. Spiller, F.C.S. 

 (Treasurer of the Photographical Society), took a photograph of the 

 group, and also obtained some negatives of the sections exposed in the 

 workings. A print from one of these, produced by the Autotype Company, 

 is given as a plate* accompanying this report. The photograph shows 

 one of the larger "pipes" in the chalk at Grays. The view is in the 

 South Central Chalk-pit, and the "pipe" is seen in shadow in the left 

 foreground of the picture — a wide and irregular- shaped cavity traceable 

 down to the floor of the pit, a distance of more than ninety feet vertical, 

 and containing deposits from the overlying Thanet sand and high-level 

 drift gravel. 



Other " pipes," in a less advanced stage of erosion, are shown in the 

 centre and to the right of the picture. 



The abandoned Western Pit, in which the South Essex Water Company 

 obtain their supply, was then \dsited. In the engine-house Mr. Walker 

 stated that, in 1860, the chalk had been worked to the level of the springs 

 in this pit over an area of some sixty-five acres, when attempts to go 

 deeper led to the discovery of an abundant supply of pure water and the 

 formation of the Company. The water passing over the gauge every 

 twenty-four hours was found to exceed 1,200,000 gallons, and even with 

 five engines at work it became necessary to brick-up fissures, so as to keep 

 the water down. Mr. Prestwich, in accounting for this volume of water 

 in an area where the superficial pervious beds do not exceed five miles in 

 extent, extends the receiving ground to the area of the Kentish chalk, as 

 well as to the northern chalk area which begins beyond Bishop's Stortford 

 and Dunmow ; considering that the Thames, which opposite Greenhithe 

 and Dartford is not, even at high tide, more than fifty or sixty feet in 

 depth, would not intercept all the springs. f The daily quantity now 

 yielded is about 1,300,000 gallons, of which 600,000 gallons is pumped to 

 waste to avert inundation. Owing to the low level to which the chalk has 

 been worked, the water is found near the surface, the engine-house floor 

 being seventeen feet above Ordnance datum, and the water in the well 

 varying from that line to eight feet below it. 



This old chalk-pit would seem to^be a capital hunting-ground for both 

 entomologists and botanists. There is plenty of undergrowth and chalk- 

 loving plants, the Clematis vitalha being notably luxuriant ; but the 

 claims of the geologists were so imperative that no time was allowed for 

 herborizing. In the sections of the Thanet sand an abundance of the 



^e>* 



* Our members will be pleased to learn that we owe this interesting and instructive 

 record of a pleasant meeting to the kindness of the three following gentlemen, who 

 reimbursed our Treasurer for the cost of the plate in the manner following : — Mr. 

 Meldola, £2 2s.; Mr. John SpiUer, £1 Is.; and Mr. Harcourt, 10s.— Ed. 



i • Report of Water-springs at Grays.' Privately printed, 1860, 



