96 retoet — 1884. 



Tenth Report of the Committee, consisting of Professor E. Hull, 

 Dr. H. W. Crosskey. Captain Douglas Galton, Professors J. 

 Prestwich and G. A. Lebour, and Messrs. James Glaisher, E. B. 

 Marten, Gh H. Morton, James Parker, W. Pengelly, James Plant, 

 I. Roberts, Fox Strangways, T. S. Stooke, G. J. Symons, 

 W. Topley, Tylden-Wright, E. Wethered, W. Whitaker, 

 and C. E. De Rance (Secretary), appointed for the purpose 

 of investigating the Circulation of Underground Waters in the 

 Permeable Formations of England and Wales, and the Quantity 

 and Character of the Water supplied to various Towns and 

 Districts from those Formations. Drawn up by C. E. De Rance. 



The Chairman and Secretary of your Committee are both unavoidably 

 obliged to be absent at the Montreal meeting, which is a source of regret 

 to themselves ; the more so that, this being the case, it has been thought 

 advisable to delay presenting their final Report on the Circulation of 

 Undersrround Waters in South Britain until next year, when the Com- 

 mittee will have been twelve years in existence. During these years 

 particulars have been collected of the sections passed through by a very 

 large number of wells and borings ; a daily record has been obtained 

 of the height at which water stands in many of these wells ; investigations 

 have been carried out as to the quantity of water held by a cubic foot 

 of various rocks, by Mr. Wethered ; and as to the filtering power of 

 sandstones, and the influence of barometric pressure and lunar changes 

 on the height of underground waters, by Mr. I. Roberts. During the 

 present year the attention of the Committee has been directed to the 

 remarkable influence of the earthquake which visited the east and east- 

 central counties of England, in March last, in raising the levels of the 

 water in the wells of Colchester and elsewhere. 



More detailed information is still required as to the proportion of actual 

 rainfall absorbed by various soils, over extended periods representing 

 typical dry and wet years. Information on these heads and on other points 

 of general interest bearing on the percolation of underground waters, 

 referring to observations made in Canada or the United States, would be 

 gladly welcomed by the Committee, and would be incorporated in their 

 eleventh and final report to be presented next year. 



Appendiv — Copy of Questions circulated. 



1. Position of well or shafts with which you are acquainted .' Xa. State date at 

 which the well or shaft was originally sunk. Has it been deepened since by sinking 

 or borin.tr ? and when ? 2. Approximate height of the surface of the ground above 

 Ordnance Datum (mean sea-level) .' 3. Depth from the surface to bottom of shaft 

 or well, with diameter. Depth from surface to bottom of bore-hole, with diameter? 

 3a. Depth from the surface to the horizontal drift-ways, if any ? What is their 

 length and number .' 4. Height below the surface at which water stands before, and 

 after pumping 1 Number of hours elapsing before ordinary level is restored after 

 pumping ? 4a. Height below the surface at which the water stood when the well 

 was first sunk, and height at which it stands now when not pumped ? 5. Quantity 

 capable of being pumped in gallons per day of twenty-four hours ? Average quantity 

 daily pumped ? 6. Does the mater-level vary at different seasons of the year, and to 

 what extent 1 Has it diminished during the last ten years ? 7. Is the ordinary 

 7vatcr-level ever affected by locnl rains, and, if so, in how short a time ? And how 



