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THE FARMER'S MAGAZINE.

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to 42lbs. per cubic foot of earth, or 378lbs. per square yard of soil a foot deep, then 378 x 4840 (the number of square yards in an acre) gives 1,829,520lbs. of water needed to saturate an acre of perfectly dry land to the depth of one foot, or about 816 tons. If we suppose that the saturation of the soil need only extend to a depth of nine inches, then about 543 tons of water would be sufficient; if a depth of only six inches, then 408 tons; and if to only a depth of four inches, then 273 tons would suffice. It appears from the report of Dr. J. Stark, that the celebrated Craigentinny Meads, near Edinburgh, are annually irrigated by the city sewage about eighteen times. For instance, a certain plot was watered in its turn, May 3 and 14, June 3 and 20, Aug. 15 and 31, Oct. 8 and 29, Nov. 24, Dec. 31; in 1846, Jan. 30, Feb. 18, March 5 and 22, April 2 and 13. Now, if we calculate that, on an average of months, 250 tons of irrigation water would suffice to saturate the soil (always par tially and sometimes thoroughly previously moistened), then it would require 4,700 tons of water to give these eighteen irrigations to an acre of land. I deem the quantities I have stated as likely to be an average amount of sewage fluid required for the irrigation of an acre of grass land to be nearly correct. In the report of Mr. George Buchanan, engineer for the irrigated meads of Craigentinny, near Edinburgh, he states the quantity of water necessary per acre to be equal to a stream of sewer fluid of 3 cubic feet per minute for 12 days of 10 hours each, or about 650 tons. It will be remarked, however, that the rewage fluid in this case had to sustain the soakage, leakage, and evaporation during thirteen days of the month of May. This slow irrigation is far from being the most economical mode of applying the sewage-the more rapid and copious application being to be preferred, as afford. ing little time for the soakage of the substratum, and the leakage from the soil into the drains, and evaporation from the surface. Mr. Buchanan also adds, "In some parts the soil consists of very stiff clay, resting on a similar substratum, and other parts of a red sand, and the sand requires nearly twice as much water for saturation as the clay." We see, then, that the amonnt stated by Mr. Buchanan of about 700 tons per acre having been used at Edindeductions burgh upon a mead, and subject to many from its saturating power, is not very widely different from the average amount of about 800 tons required, according to Professor Schubler, to saturate the same extent of nearly chemically dry earths. Then, again, by avoiding the soakage and drainage waste of twelve days, and taking the average of moderately retentive soils, a very material saving would undoubtedly be accomplished; and, moreover, by raising the sewage fluid to the contemplated elevations, it would be available, as at Edinburgh, for the use of the irrigation a second time. The use of sewage waters a second time, in irrigation, is an old-established practice in Italy. In the celebrated meads of the neighbourhood of Milan, "the water of the draining channel," says Count Arrivabene, "is collected into another channel, which conducts it to irrigate another meadow in a similar manner. Upon the whole, therefore, I am inclined to think that the calculated fiantly

4,700 tons per acre annually is a tolerable approxi-
mation to the truth."

In

In the experiments instituted at Rugby by the members of the Royal Commission the amount applied per acre has been in these experiments 3,000 tons, 6,000 tons, and 9,000 tons per annum. these trials two material objects were hoped to be attained, viz. :1. To ascertain the amount of increase of produce from the application of different proportions of sewage to grass. 2. The most beneficial mode of using the grass produced, whether for milch cows or for fattening stock, given either by itself or with other food. These experiments were attended with very valuable results, although they were conducted under considerable difficulties, and the amount of sewage available was considerably less than was intended. The following results are given in the words and figures of the report

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Two fields were employed in these experiments, viz., one of five acres, the produce of which was intended to be devoted to the feeding of oxen, to which the sewage was in these trials first applied on the 6th March, 1860; and one field of ten acres, to which the sewage was not conducted until the 1st of April. The chief results obtained were, that in the five-acre field the produce of grass obtained from four plots was as follows:

1.

2.

3.

4.

Plot not dressed with sewage produced,
in two cuttings, of green grass per

acre

Tons. Cwt.

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Plot dressed with 3,000 tons of sewage
per acre, in four cuttings.....

14 16

1

Plot with 6,000 tons, in four cuttings. 27
Plot with 9,000 tons, in four cuttings. 32 17
In half of the ten-acre field-

1.

2.

3.

4.

Plot, soil undressed, produced in two

cuttings..

Plot dressed with 3,000 tons per acre
produced in four cuttings....

Tons. Cwt.

8 18

...

15 16

Plot dressed with 6,000 tons in four
cuttings produced....

22 15

26 13

Plot dressed with 9,000 tons, in four
cuttings.....

So that the increase of grass from the application of
every 1,000 tons of sewage was, on an average,
between three or four tons per acre.

In the experiment made with the grass in fattenconsumed, during sixteen weeks, per head daily ing cattle ten Hereford oxen were employed. They acre was sufficient to keep an ox, from 105 lbs. of the grass; so that the grass of each

The soil simple

Weeks. 32.9

The soil with 3,000 tons of sewage. 45
The soil with 6,000 tons
The soil with 9,000 tons

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The value of the increase of the oxen in live add to frostiede mos weight per acre, at 4d. per lb., was as follows Grass from soil simple.ws.sdl milli vd 24 32 Ditto 3,000 tons Ditto a 9f0,000 tons. do 240 91T Ditto ad 39,000 tons.si 18 v0kros 80 that the value of the live weight from the int creased prodire of 1,000 tons of sewage was fron Hollay 199 the grass land dressed with

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From grass without sewage, at ls. 6d. per gallon

...

......

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11 13 10 18 14 10 26 18 7

7

The 3,000 tons of sewage grass The 6,000 tons of sewage grass The 9,000 tons of sewage grass 31 11 The increased value of the milk from the application of each 1,000 tons of sewage to the grass was therefore about £4 12s.

As some doubt had been entertained as to the comparative value of the milk from the cows fed with the grass produced with and without sewage, the composition of 100 parts of the milk from the cows fed on the grass from the unsewaged and the sewaged grass was ascertained by Professor Way. He analyzed nine samples of each. The mean of these was as follow:

Casein, or cheese Butter

Sugar of milk, &c. Mineral matter

Total solid matter Water...

With grass. Unsewaged. Sewaged. 3.246 3.241 3.604 3.430 4.405 4.218 0.753 0.776

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Phosphoric acid

30

In almost all the investigations into the agricultural value of sewage which have hitherto been made too little attention has been paid to the value of the mere water of the liquid. In the experiments carried on at Rugby, the water bestowed upon the grass in the sewage was equal to a rainfal of about 30, 60, and 90 inches per annum. Now, if this large amount of liquid had been only rain water, the increased produce of grass would have been very considerable. The weight of grass produced in the east of England, moistened by an annual rainfal of 20 inches, is, we all know, very inferior to that yielded by similar soils on the western side of the island supplied with a rainfal of 40 inches, and vastly inferior to the produce of the meads of the chalk formation annually watered with at least 50 inches of the bright waters as pure as when they issue from the chalk.

Then, again, it is not merely the amount of the organic and other matters conveyed into the grass which should be valued, but their thorough diffusion in the soil, and the state of solution in which they come in contact with the roots of the plant, is also a very material element in the case. The amount of guano which the Peruvian cultivators sprinkle over their fields is said to be very small in amount, but then they always irrigate the land as soon as the guano is spread. Every English farmer is aware how much more valuable is the effect of this manure, when he employs it in heavy rains; for its valuable portions are then dissolved in the rain water, and diffused through the soil. Irrigating with sewage accomplishes a similar object with far more certainty.

In the case then of lands so situated that the sewage can be conducted on to them by its own gravity, the importance of its employment in irrigation need hardly be advocated. In those many situations where the outfall of town sewers is too low for the sewage to be thus conveyed on to the land, recourse must be had to the steam engine and the pump. Now, supposing it is necessary to raise such a considerable amount of sewage from a lower level to the surface of the soil, then the following observations as to the consumption of fuel required to raise water to various heights may be useful: for these I am indebted to Messrs. Ransome and Sims, of Ipswich. The greatest effect in pumping water is found in the Cornish pumping engines: now, the average of these fire engines, reported in June, 1851 (being twenty-five

engines) is 62,000,000 lbs. of water raised one foot high by the consumption of 1 cwt. of coals. These engines are very large, the steam is used expansively, and condensed, and every appliance adopted to economise fuel. Probably we shall not be far from an average, if we estimate that the small engines used for agricultural purposes will not perform more than one-fourth of this duty," or say, 16,000,000 lbs. of water raised one foot high by the use of 1 cwt. of coals. It must be understood that the same weight of coal will lift half the water to twice the height, or one-fourth the water to four times the height, and so on. Now, supposing that we have to lift the water from a stream to the portion of a field which is ten feet above the level of the river, then 1 cwt. of coal will lift to that height one-tenth of 16,000,000 lbs. of water, or 1,600,000 lbs. A gallon of water weighs 10 lbs., and therefore 160,000 gallons will be lifted, or, as 224 gallons weigh a ton, 714 tons of water may be raised 10 feet with the consumption of only 1 cwt. of coal; and this is almost exactly equal to an inch in depth over seven acres, or an average fortnight's rain in the southern and midland counties of England.

The subjoined table gives the gallons of water which may be lifted to various height by the consumption of 112 lbs. of coal; the pumping apparatus being good, and adapted to the power of the engine, the calculation being based upon the preceding datum of 1,600,000 lbs.

The use of sewage in irrigation, as I long since ventured to predict, will, there is little doubt, be chiefly confined to grass lands. Of this opinion is Professor Voelcker, who on this subject recently addressed the members of the Royal Agricultural Society. In most of the conclusions to which he arrives I heartily concur, and in none more so than when in the course of his able lecture he had occasion to inquire why it is that grass is especially benefited by the sewage of towns. It is so, he added, because it is a quick-growing crop, which allows us to apply a fresh quantity of fertilising matter as soon as a given quantity is exhausted. We can repeatedly manure the grass crop, but we cannot the cereal crop. We should never get our wheat ripened if, after it has passed through its grassy condition, and arrived to some extent at maturitywe should never get the grain formed, if we were to apply sewage to it Neither can we well apply sewage to market produce; at least not on most soils; for sewage has a tendency to close up the pores of the soil, and to encrust it, which is a great practical inconvenience. We should also remember that we must dispose of the sewage of a town at all times of the year, and that we must therefore apply it in very large quantities at a time. Now, to grass lands we can apply very large quantities, because grasses grow very rapidly, and enable us to give a fresh dressing or a large dose of manure.

Upon the importance of these scientific researches I need hardly remark. The intelligent readers of One cwt. of coal then will raise 1 foot.. 1,600,000 this widely circulating magazine are well aware,

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gallons.

800,002 that in working out the great problem as to the 533,000 best disposal of the sewage of towns, two noble ob400,000 jects are to be attained-1st, the improvement of 320,000 the public health; and 2ndly, the increased fertility 266,666 of our cultivated soils. The experiments to which I 228,571 have drawn the reader's attention will materially 200,000 tend to promote these great objects, for they will 177,777 enable the cultivator to proceed on safer, because 160,000 still better understood ground. Of one conclusion 145,454 I am quite certain-that if the course of the streams 133,333 of sewage, now commonly worse than wasted, are 123,076 only so altered as to be available to the skilful agri114,444 culturists of our country, they will need no ar106,666 guments to induce them to turn those now noxious 130,000 streams to a nationally important purpose.

ON HARVESTING CORN CROPS.

BY A PRACTICAL FARMER.

The present season is as yet an unsettled one. Stormy winds and occasional rains prevail to a great extent. The winds have certainly done considerable injury to the whole of the corn crops, but more particularly the wheat and bean crops. The former is greatly damaged, large breadths being prematurely laid; and vast numbers of individual stems are broken down at the root, and are strewn throughout the crops. The bean crop is not so much hurt; but great numbers of stalks are broken down, and much injury is done to the general crop by hard flogging. The oat and barley crops have both sustained much damage, the former the less of the two; but very many heads of barley are

strewn about, and a vast many others sadly whipped by the wind.

Seeing this is so, it may be useful to your farming readers to offer a few plain suggestions for their consideration, on the best modes of harvesting their corn crops. It is to be noted with some concern, if not censure, that farmers, as a body, are too much wedded to their own practices. "I do so-and-so." Each has his own peculiar method of business; and it is seen in the harvesting of corn crops more prominently than in any other department of it. Now I want all and every established customary practice to be looked at dispassionately, with the view to ascertain if any improve.

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