74 SCIENTIFIC SURVEY OF LEICESTER AND DISTRICT 
carried on by a private company for the supply of gas for lighting purposes. 
The water undertaking in Leicester is to-day supplied from ‘Thornton 
Reservoir, completed in 1854 ; Cropston Reservoir, completed in 1870 ; 
and Swithland Reservoir, completed in 1894. From these reservoirs the 
undertaking can obtain 6 million gallons per day, but it was realised many 
years ago that this supply was not sufficient to meet the ever-growing 
demand. 
Eventually a bill was promoted in Parliament in 1899, upon the advice 
of the late Mr. John Breedon Everard, authorising the impounding of 
water from the Valley of the Derwent in Derbyshire. The cities of 
Nottingham and Sheffield and the borough of Derby at the same time 
considered they were entitled to a supply from this area, and the result 
was an arrangement whereby a joint board was established by an Act of 
Parliament passed in that year. The Derwent Valley Water Board to-day 
consists of representatives of the corporations of Leicester, Nottingham, 
Derby and Sheffield, and from this source Leicester (being the pre- 
dominant partner) receives an average daily supply of approximately 
seven million gallons. ‘The whole of the works authorised to be con- 
structed have not yet been carried out, but when they are completed, the 
joint board will be enabled to supply an amount of water which will 
furnish to Leicester an average daily amount of 10} million gallons. 
The water obtained from the Derwent is excellent and, following upon 
filtration at Bamford (the southernmost point of the Derwent watersheds), 
the Leicester portion is delivered at Hallgates, some five miles out of the 
city. At Hallgates the water is subjected to mechanical pressure filtration, 
during which process it is decoloured and rendered alkaline. The first 
process renders the water suitable for drinking and manufacturing pur- 
poses, and the latter process is carried out as a prevention against plumbo- 
solvency and action upon iron pipes. 
Gas AND ELECTRICITY. 
It has already been observed that the gasundertaking of the Corporation 
was acquired contemporaneously with the water undertaking. Originally 
operated by a private company, it has since 1878 formed part of the 
Corporation’s activities. ‘The undertaking has developed extensively in 
the course of years, and. to-day supplies the city and a considerable area 
beyond with gas for power, industrial, and domestic purposes. There 
are two large works, one at Aylestone, where the plant established is of 
the Glover West vertical retort system, of a producing capacity of 
105 million cubic feet per day, together with carburetted water gas plant, 
capable of producing 6} million cubic feet per day. ‘This includes the 
latest automatic plant of Messrs. Humphreys & Glasgow, capable of 
producing 2+ million cubic feet per day. The second works, at Belgrave, 
is also equipped with Glover West vertical retort coal gas plant, of a 
producing capacity of 4 million cubic feet per day. The undertaking 
has been financially a great success, and the Corporation have always 
endeavoured to keep their plant in good condition and up to date. 
Originally, the electricity supply by the city, under the powers of a 
Provisional Order obtained in 1891, formed part of the undertaking 
