ON THE CIRCULATION OF UNDERGROUND WATERS. 213 



Eighth Report of the Goni'rnittee, consisting of Professor E. Hull, 

 the Eev. H. W. Crosskey, Captain Douglas Galton, Professors 

 Gr. A. Lebour and J. Prestwich, and Messrs. James Glaisher, 

 E. B. Marten, W. Molyneux, Gr. H. Morton, W. Pengelly, 

 James Plant, James Parker, I. Egberts, C. Fox Strangways, 

 Tuos. S. Stooke, Gr. J. Symons, W. Topley, Tylden- Wright, 

 E. Wethered, W. Whitaker, and C. E. De Eance {Secretary), 

 appointed for the purpose of investigating the Circidation of the 

 Underground Walers in the Permeable Formations of England, 

 and the Quality and Quantity of the Water supplied to various 

 Towns and Districts from these for')nations. 



Eight years have elapsed since this Committee commenced to investigate 

 the circulation of underground waters, and the quantity and character of 

 water supplied to towns and districts so derived. 



From 1874 to 1878 the Triassic and Permian formations were alone 

 under consideration ; in that year the Jurassic rocks were added to the 

 scope of the enquiry, which at the York meeting was enlarged to include 

 the whole of the permeable rocks in England and Wales. 



The Triassic and Permian rocks of Devonshire are described in the 

 first, fifth, and sixth reports ; of Somersetshire in the first ; of Leicester- 

 shire in the first, fourth, and fifth ; of Warwick in the second, fourth, 

 and seventh ; of Nottingham in the second and sixth ; of Cheshire in the 

 second, fourth, and fifth; of Lancashire in the first, second, third, fourth, 

 sixth, and seventh ; of Yorkshire in the first, second, third, sixth, and 

 seventh ; of Shropshire in the sixth. ^ 



Through the removal to South Africa of the member of the Committee 

 taking charge of Staffordshire, this district is still incomplete, but some 

 information as to the Bui'ton-on-Trent area is given in the first report. 



In Devonshire the enquiry was carried on by Mr. Pengelly, F.R.S., 

 supplemented by details obtained by Mr. Stooke, C.E. The Triassic rocks 

 of the district have been made the object of careful study by Mr. W. A. E. 

 Ussher. From his investigations it would appear that the sequence ex- 

 hibited has more in common with the Trias of the French side of the 

 English Channel than with that of the midland counties. In Devonshire 

 and Somersetshire the sandstones and conglomerates appear to have been 

 deposited in a distinct basin to that north of the Mendips, the Keuper 

 marls being alone common to the two districts. 



The basin south of the Mendips is remarkable for having a series of 

 marls intercalated in its sandstones, called by Mr. Ussher the ' Middle 

 Marls ' ; these underlie sandstones beneath the Keuper marls. The con- 

 glomerates have a distinctly local character, and when present are plenti- 

 fully water-bearing, as are the sandstones, though to a somewhat less 

 extent. 



Private supplies are obtained by wells at Torqnay, where the water- 



' Beport of Brithli Association for 187.5 (Bristol) contains first report ; that for 

 1876 (Glasgow) the second; that for 1877 (Plymouth) the third; that for 1878 

 (Dublin) the fourth ; that for 1879 (Sheffield) the fifth ; that for 1880 (Swansea) the 

 sixth ; and that for 1881 (York) the seventh. 



