228 



THE FARMER'S MAGAZINE. 



including interest, labour, and fuel, and which is 

 more than in the case of the Edinburgh works. 

 The water in the case of the hose and jet has to be 

 pumped at a pressure to enable it to be projected to a 

 considerable distance from the hose, otherwise the 

 amount of pipes and hydrants would be increased to an 

 almost infinite quantity, and the cost would be enormous. 

 On the contrary, by the gravitation system, when water 

 is pumped by the engine, the weight of the water only 

 has to be lifted to the height required by pumping, at a 

 pressure equal to a height not very much greater than 

 that of the highest part of the land, and which is the 

 point where the discharge of the water takes place from 

 the end of the pipe leading from the engine. Also the 

 amount of channels for its distribution is very great, 

 and their combined area is very large in comparison with 

 the area of one pipe of 3 inches diameter, which is the 

 area for the water to pass with the hose and jet system. 

 While the evidence from various places of thecostat 

 which the liquid is put on shows in one case that it is 

 done at rather more than 0|d. per ton, at another at Id., 

 and by the greater number of farms at 2d. per ton, it 

 can be shown by the practical rules used by hydraulic 

 engineers, that for all farms contiguous to the rail, and 

 such only at first would be contemplated, the water 

 could be raised and distributed at 20 tons for Id., in- 

 cluding interest for engineers and machinery, and all 

 labour and fuel (which charge, I may repeat, is more 

 than is practically found necessary for the purpose at 

 Edinburgh). There is also, however, the interest upon 

 the pipe-works and gutters upon the ground to be con- 

 sidered, which if added makes the total cost Id. for 

 14 tons. 



The health of the inhabitants near or upon the works, 

 is a question that used to be asked in reference to the 

 propositions made at various times to follow the Edin- 

 boro' system, but this has been so completely negatived 

 by the various competent authorities and medical men 

 who have examined the question, either at Edinboro' or 

 Milan, that I need not further allude to it. In the 

 system I propose, as no amount at one time will be 

 put on more than soaks away into the drains, and is at 

 once pumped back into the sewers, there will be no 

 water left standing on the surface. If, however, it 

 should be asked whether, with the amount proposed, 

 the water would percolate fast enough through a reten- 

 tive soil, I need but say that in Mr. Bailey Denton's 

 very valuable experiments at Hinxworth, carried on for 

 twelve months, which land he purposely chose for his 

 experiment, he tells us, because it was the stifFest land 

 that he was acquainted with, and is styled in the report 

 "very stiff clay, and impenetrable," a proof will be 

 found for those who choose to study the subject, that 

 no such fears need be anticipated with the amounts pro- 

 posed. On one part of the estate the land had been 

 drained 4 feet deep, 25 feet to 27 feet apart; another 

 part of the estate was not drained. Test holes (or wells) 

 were made in each, to see at what level the water always 

 stood in the ground, and the amount of discharge from 

 the drains registered. On January the 9th, there was 

 no rain, the drains discharging 125 gallons per acre in 

 the twenty-four hours, the water standing 4 feet 3 

 inches from the surface of the drained land, and 1 foot 

 3 inches from the surface in the undrained land. On 

 the 10th itpouredwithrain, 12,200 gallons peracre in the 

 twenty-four hours ; immediately the drains discharged 

 5,150 gallons, and the water rose in the test holes to no 

 higher a level than 4 feet from the surface ; in the un- 

 drained field it rose to within 5 inches of the surface. 

 On the 11th, it rained 6,780 gallon; it discharged 4,000 

 gallons. On the 12th, it rained 3,660 gallons ; it dis- 

 charged 1,990 gallons. On the 13th, there was no rain, 

 tbe pipes discharged 1,250 gallons. On the 14tb, " 



tb^ie 



pipes discharged 600 gallons ; on the 15th, 3?3 gallons; 

 and continued daily at about that rate of discharge. 

 The test holes during this time never rose more than 1 

 inch above 4 feet in the drained land. Here we see 

 12,200 gallons, or 50 tons, per acre, carried down at once 

 to 4 feet from the surface, and the excess immediately 

 passed away, and this in the middle of winter. Mr. 

 Mechi often puts on 25,000 gallons, which is 100 tons, 

 upon an acre in five hours ; but the experiment of Mr. 

 Bailey Denton in the winter, when the ground is not 

 dry, is more valuable for our purpose. From these ex- 

 periments it is quite plain, that the amount I should re- 

 quire to put upon an acre in the twenty-four hours 

 would never stand upon the surface, while the soil pro- 

 posed to be used is of a much more porous description. 



It has been generally thought that if poor sandy land 

 could be got, it would be profitable to carry out a 

 system of irrigation with London sewage. I believe that 

 the comparative increase of the value of the acre of land 

 would be greater than with good alluvial soils, but I 

 believe that the amount per acre of crop, or the amount 

 of benefit that can be got out of a certain amount of 

 sewage, will be greater with alluvial soils ; and if this is 

 true, it is valuable to remember it, because by far one 

 of the greatest difiiculties with reference to the applica- 

 tion of the metropolitan sewage will be found to be the 

 difficulty of getting a space small enough to get the 

 most value out of the sewage. One has but to look at 

 the Ordnance map to be convinced of this. The ques- 

 tion will not occur then, how large a surface can we 

 benefit at a small amount each acre, to gain a profit on 

 the whole ? thus giving ourselves an impracticable 

 outlay of money to take pipes many miles into the 

 country, till in fact we find ourselves in the district of 

 arable land crops, to farmers who prefer valuable solid 

 manure carted from London for little money, to weak 

 liquid manure, which is suitable to hardly any of their 

 crops, and which liquid manure is, on the other hand, 

 good for grass just because it is weak, while also the 

 mixture being weak the grass must have a large quantity 

 to produce a large crop. In addition, it should be re- 

 membered, grass always holds a high value near a large 

 town. It is necessary to retain these points in view by 

 those who intend to consider the subject. There has 

 been much harm done to the question, and calm con- 

 sideration has been banished by the outrageous proposals 

 of some men. One gentleman, whose pamphlet has 

 been, I believe, most prominent, proposed 1,700,000 

 acres for the disposal of the sewage, or 2,734 square 

 miles. The amount of pipes, the height to which the 

 liquid was to be pumped, and the horse-power in engines, 

 besides objectionable reservoirs, would in the annual 

 charge for interest and cost for working the engines, 

 have been stupendous. He proposed to charge every 

 farmer £1 per acre, and to supply him with 50 tons of 

 sewage, which at the full value, according to analysis, 

 is only equal, at 2d. a ton, to 8s., while the farmer 

 was, besides paying this, to beat all the cost of distribut- 

 ing the manure. The amount of capital required was 

 stated at little less than 9,000,000 sterling. For the 

 present requirements of the metropolis not one-hun- 

 dreth part of the above land would be wanted to use the 

 whole sewage of London. If we are content at present 

 with thinking of absorbing only one-half of the 

 125,000,000 tons of sewage, which we shall have dis- 

 posable per annum, 6,000 acres will be sufficient for the 

 purpose. Now, this is a very attainable quantity of 

 land, four thousand acres to the north of the Thames 

 and two thousand to the south, might easily be obtained ; 

 and the amount of pipes and cost on account of 

 the distance of any part of this surface would not be 

 increased much beyond the original estimate which I 

 have given, certainly not increased £2 per acre per 



