APPLICATION TO AGEICULTURE. 141 



from it, and made to flow into another. As much of the water 

 as possible is run off from the mud, and the latter is drawn into 

 the acidifying tanks. From these the semi-dry mud is further 

 dried bv heat in revolving? iron cylinders, which discharoe it at 

 one end. The dry powdery mud is then packed into bags for 

 transport. 



The okl process of precipitation by lime and other processes 

 were, we believe, tried here and elsewhere ; but the Aylesbury 

 Company have been working for the past seven years in the 

 manner described, and the Local Board have recently renewed 

 the af^reement for another seven years at an increased subsidy. 

 The cost of the works is about 10s. per head of the population 

 for small towns, and for larger places it is much less. The cost 

 of works is estimated at £8000 for 50,000 inhabitants, and the 

 cost of working (viz., materials, labour, &c.) depends largely 

 upon the position of the town, occ. The A. B. C. Company 

 undertake to effectually treat and dispose of the sewage of any 

 town, entirely relieving the authorities from all trouble, risk, 

 and responsibiUty, for a fixed annual subsidy. There is no tixed 

 scale, but generally the payment amounts to about Is. per liead, 

 if suitable works are constructed by the town. It would have 

 been of great advantage to many towns, if the Aylesbury plan 

 had been adopted instead of purchasing or renting a sewage farm. 



The sewage is all dealt with at Aylesbury, except only in 

 times of heavy rains, when the sewers are relieved by storm 

 overflows. As in too many other towns, the storm water is 

 carried into the sewers, and no process can cope with the 

 immense quantities of su'jh water after heavy and continu- 

 ous rains. Of course, the sewage is at these times so largely 

 diluted, that after the first flushing of the sewers, it is very little 

 worse than the rivers in flood times. Still at these periods, 

 about three times the ordinary average dry weather flow is dealt 

 with, anil much more could be done with additional tanks. In 

 this respect the Aylesbury plan has the advantage of irrigation 

 farms, inasmuch as when drenched with rain, sewage cannot be 

 distributed over them without detriment to the crops. 



The obliging and intelligent Secretary of the Company, Mr 

 Stevens, states that Aylesbury is the only place where the A. B. C. 

 system is actually in operation at present, but several towns 

 have the system under consideration. The Company patented 

 the invention, and in the evidence bef(»re the Committee of the 

 Privy Council, particulars are given of the materials and of the 

 ])rocess of ]»urification. 



Clay, which is by far the largest substance in use, carries 

 down tlie suspeniled matter, the alum coagulates the clay, to 

 whirh the blood also contributes, and the animal charcoal 

 purifies the materials and absorbs the gases. The result is that 



