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E. G. MAWBEY. Land Utilisation of Sewage. VIII Internationaler 

 Landwirtschaftlicher Kongress. Wien, 21-25 Mai 1907, Referate, 

 Sektion V-VII, Band III, Sektion V, Rapport 2/B. Wien, 1907. 



The main conclusions arrived at by the author are: 



" The trend at the present time in the British Isles is towards 

 artificial treatment of sewage, chiefly by tanks and bacteria beds, 

 because of the many instances where suitable land is not available, 

 or the cost is entirely prohibitive, and because of some prejudice 

 against sewage farms through mismanagement, etc.; also because 

 artificial processes can be more uniformly controlled in all weathers. 



" The ruling factors which determine in each case the method 

 of treatment to be adopted are the local conditions such as the 

 situation, levels and nature of available land, its cost and proximity 

 to inhabited areas, the nature of the sewage, and particularly by 

 which method the sewage can be rendered harmless, without 

 nuisance in treatment, at the lowest cost to the community. 



"Most soils will purify sewage if the quantity applied is in pro- 

 portion to the purifying capacity of the land, which, however, in 

 some cases may be too small to justify land treatment alone. 



"The best effluents, both chemically and bacteriologically, are 

 obtained from light loamy soils overlying a porous subsoil such as 

 gravel, or coarse gravelly sand. 



"The difficulties caused by the heavy clay soil at Leicester have 

 been overcome and satisfactory effluents obtained by the method 

 conceived and adopted of providing a separate and independent 

 system of drainage for each field below, at which the drain effluent 

 can be run on to the surface of the lower land again and again 

 for further treatment, and when sufficiently purified, discharged 

 into the effluent drain close by. 



"Low-lying flat clay land would not be so suitable for this 

 treatment. 



" Crude sewage can be treated on very light porous land, but 

 there are inevitable and serious drawbacks to this method with all 

 kinds of soil. 



" In the author's experience and practice, considerable success 

 has been achieved by the clarification and preliminary purification 

 of sewage by bacterial treatment in tanks and first contact bacteria 

 beds, and then by final purification on old pasture land, from which 

 excellent effluents are obtained and the fouling of the grass by 

 sewage matter avoided. 



