360 
8. By this experiment, which has been two years in opera- 
tion, it is found that an Income of £200 per annum might be 
derived from the town of Aylesbury, if the necessary number 
of tanks were constructed to purify the sewage from the re- 
maining sections of the town. 
9. The commercial test of the value of the manure is the 
ready and increasing sale that is found for it, and it is interest- 
ing to know, (as collateral evidence,) that the " Metro- 
politan Sewage Manure Company," having failed in their 
original objects, are now supporting the establishment at 
Stanley Bridge, by saturating peat charcoal with London 
Sewage, and selling it at £4 per ton. 
Extract from Mr. Tuffnell's report for 1852 to the Com- 
mittee of Council on Education : — 
" The land attached to the North Surrey School, and 
cultivated by the boys, has been extremely productive." 
After detailing the results, Mr. Tuffnell proceeds : " The 
flow of liquid manure from a population of 700 persons, where 
all the ordinary operations of washing, &c., were also con- 
tinually going on, was, of course, considerable. Great part 
of this was used in irrig-atingf the land, and to this the 
large crops were undoubtedly attributable. But the quantity 
the town of Aylesbury had unfortunately given another proof of being two 
centuries behind-hand. The beautiful apparatus erected by Mr. Yarrow had 
been destroyed. Whilst it was in operation, the public could travel over that 
part of the road with comfort and satisfaction. They had now diverted that most 
offensive drain across the road, and its contents were discharged into a field on 
the north side of the road at a distance, he should say, of not more than two 
hundred yards from the high road, which rendered the atmosphere in the vicinity 
of it of the most offensive character ; whereas, when the filtering apparatus was 
in operation, not the slightest taint in the air was perceptible to the passers by." 
Mr. Yarrow said, " it was well known that Croydon had always been the pet 
town of the Board of Health, and every known improvement had been carried 
out there, the whole of the sanitary works being completed under its sanction. 
In Croydon there were about 600,000 gallons of sewage per day, and there they 
had the best advice as to the means of conveying it away ; but, notwithstanding 
all the advantages they possessed, it had ultimately been determined to use char- 
coal filters. An advertisement had recently appeared in the papers for sixty tons 
of peat charcoal per month ; and the manure produced might be taken on the 
average at double the quantity of charcoal used." 
