igS SEWAGE AND ITS PURIFICATION 



and ashes sifted out was found to be one-seventh that of coal. 

 The work, however, was discontinued, as the disinfection or 

 sterihzation of the various products added considerably to the 

 expense. 



The Bury (Lancashire) Corporation, following the example of 

 a few other towns, recently arranged for the distribution to 

 shops and offices in the town of large bags, into which is placed 

 the waste paper of the establishment, the full bags being 

 collected periodically, and exchanged for empty ones. During 

 the four months in which this system has been in operation 

 there has been collected paper which realized, when sold, 

 about £30} 



4. Reduction, so called, applies more particularly to certain 

 portions of the refuse and to certain kinds, and effects utilization 

 by extraction of grease by steam or naphtha, the residue being 

 ground and dried for fertilizer stock. In the United States in 

 1902, according to a report of the American Public Health 

 Association, vol. xxix., " reduction " plant was in use in nineteen 

 cities, and was worked by private companies under contract, 

 the Arnold process being the most frequent. It was concluded 

 in this report that (i) economically the two systems, reduction 

 and cremation, are fairly well balanced, but the former gives 

 rise to a nuisance, whereas the latter can be conducted without 

 it ; (2) experience shows that the English and German system 

 of burning the ashes and garbage together in cellular in- 

 cinerators, with sloping grate bars for preliminary drying, and 

 forced draught, is cheaper and more satisfactory than the 

 American (single large chamber and horizontal grate) ; (3) the 

 disposal of garbage in water or on waste land is strongly 

 condemned. 



5. Burning. — Although this is the most perfect means of 

 sterilization, the difBculties have been : 



(a) The large and varying proportion of water, which often 

 renders the material incombustible without being dried ; the 

 nuisance occasioned during drying in air ; and the cost of the 

 fuel for drying artificially. 



{b) The low combustibility of the material, even after desic- 

 cation, requiring assistance by coal, special furnaces, and much 

 labour. 



(c) The offensive nature of the gases evolved during the 

 burning. 



1 Public Health, September, 1905. 



