358 KEPORT— 1887. 



trolytic Polarisation.' — See the Philosophical Magazhie. For abstract, see Trans, of 

 Sections. 



Professor M'Leod, ' On the Electrolysis of a solution of Amnionic Sulphate.' — 

 See the Journal of tlw Chemical Society. 



Professor S. P. Thompson, ' On the Electro-deposition of Alloys,' and ' On the 

 industrial deposition of platinum.' 



Thirteenth Report of the Committee, consisting of Drs. E. Hull and 

 H. W. Crosskey, Sir Douglas Galton, Professors J. Prestwich 

 and Gr. A. Lebour, and Messrs. James Glaisher, E. B. Mar- 

 ten, Gr. H. Morton, W. Pengelly, James Plant, I. Egberts, 

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

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

 a-ppowited 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 sup- 

 plied to various Totvns and Districts from these Formations. 

 [Drawn up by C. E. De Kance, Reporter.) 



Your Committee are of opinion that, looking at the large number of 

 details of borings collected since their last report, and to the national im- 

 portance of our underground- water stores, which have not failed in any- 

 public supply of importance throughout the kingdom, in spite of the 

 exceptional drought, it is desirable that their labours be continued until 

 there appears reasonable probability that the whole of the information on 

 the subject has been procured, and that future observations will simply 

 duplicate the knowledge already obtained. 



Many of the problems to be solved have only as yet reached the pre- 

 liminary stage of inquiry, while others require accurate observations by 

 numerous observers, under varying conditions of character of soil, 

 amounts of rainfall, and local conditions. 



Cheltenham Water Siipply is derived from springs issuing at the base 

 of the sands of the Inferior Oolite, which yield a water described by the 

 Rivers Pollution Commission as ' palatable, wholesome, and well suited 

 for dietetic purposes, and is also much softer than most spring waters 

 from the same strata.' Mr. McLandsborough, C.E., the engineer to the 

 works, states the reservoir holds 200 days' supply, and is delivered on 

 the constant system ; he has gauged the springs on the hills above the 

 reservoirs since 1864, and has never found them fail : during the severe 

 drought of 1884 they yielded a volume equal to half the average daily 

 supply of the period gauged. The minimum yield of the spring was in 

 December of 1884, when the reservoirs were more than half full, and 

 would have enabled the corporation to give a full supply if the drought 

 had continued into the spring of 1885. In the Eleventh Report of your 

 Committee, by a most unfortunate misprint, the reservoirs are described 

 as ' dry ' during the drought of 1884, instead of ' short,' as reported by a 

 correspondent, in which statement he was obviously incorrect. Your 

 Committee much regret that the condition of the Cheltenham Water- 

 works should have been misrepresented by them, as they were fully- 

 aware of the ample supply and pure quality given to the town by the 

 corporation, the purity of which has been testified to by Drs. Allen 

 Miller, Frankland, Way, and Tidy, and Professor Voelcker. 



