Refuse Disposal and Sewage Purification. 23 



per B.T.U. The Corporations of St. Helens and Llandudno 

 are arranging to use current from their destructor stations for 

 working the tramways, and at Bradford electric current is 

 supplied to the tramways at one penny per B.T.U. , and at that 

 price yields a profit of 25 per cent. This question has an 

 important bearing on the economic and efficient administration 

 of municipal matters. At St. Helens the Corporation are 

 laying and equiping a network of tramways, leasing them to 

 a private company, and supplying current at a nominal price, 

 to enable a large scattered industrial population to have rapid 

 communication at cheap fares. Professor Forbes estimates 

 ashbin refuse to contain 50 per cent, breeze and cinders, 25 per 

 cent, incombustible matter, and 25 per cent moisture. The 

 non-combustible elements, chiefly mineral, leave the furnace in 

 the form of hard clinker, which is perfectly innocuous and 

 serviceable for concrete, mortar, and — when mixed with a 

 proportion of fine dust from the flues together with cement — 

 can be formed into paving slabs, both they and the mortar 

 being produced at a cheap rate, and adding to the profit 

 bearing revenue derived from destructor stations. From an 

 economic standpoint water-carriage for sewage is a wasteful 

 system, as Sir William Crookes estimates this national loss to 

 the soil of nitrogen, phosphates, and potash at ^16,000,000 per 

 annum. 



Sewage purification involves biological problems, and in a 

 great measure it is due to the researches of Mr. S. R. Lowcock, 

 Mr. W. E. Adeney, and Mr. Donald Cameron that general 

 acceptance is given to the idea that bacteria are the scavengers 

 of nature. Dead organic matter is perpetually undergoing 

 decomposition into the gaseous and sahne compounds that, in 

 the economy of nature, go to sustain vegetable life, this 

 decomposition being brought about by the agency of micro- 

 organisms of various kinds, which may be either putrefactive 

 or by oxidation, the latter being the work of those healthy 

 micro-organismal scavengers that cover the whole surface of 

 the earth, and without whose beneficient work all terrestrial 

 life, vegetable and animal alike, would cease to be. 



