1S36.] 



FARMERS' REGISTER. 



657 



be prevented as much as possible. For this end 

 the dung should be kepi dry and unexposed to the 

 air; for the moisture, and contact with the 0x3 gen 

 of" the atmosphere tends to excite fermentation. 

 To protect a heap from rain, a covering of com- 

 pact marl, or of a tenacious clay, should be spread 

 over (he surface and sides of it. Watering dung- 

 hills is sometimes recommended for checking fer- 

 mentation; but this practice, although it may cool 

 the dung for a short time, is inconsistent with jusl 

 views, for moisture is a principal agenl in all pro- 

 cesses of decomposition: dry fibrous matter will 

 never ferment. Water is as necessary as air to 

 the process, and to supply it to fermenting dung is 

 to supply an agent which will hasten its decay.' 

 'If a thermometer plunged into the dung does not 

 rise above 100 3 of Fahrenheit, there is little dan- 

 ger of much aeriform matter flying off; if the 

 temperature is higher, the dung should be imme- 

 diately spread abroad.' 



There is no ground lor contesting the fact that 

 a large quantity of fluid and of gaseous vapor is 

 allowed to escape during the common process of 

 reducing farm-yard manure to the state of short 

 muck; but the practical inference deduced there- 

 from can only be proved by experiments on a 

 much broader scale than those which have been 

 yet submitted to the public. 



The separation of a rich fluid substance, drain- 

 ed from a mass of dung, must, doubtless, dimin- 

 ish the fertilizing power of the manure in the pro- 

 portion in which it has been extracted; but these 

 drainings can either be preserved in tanks, and af- 

 terwards either thrown over the heap or applied to 

 the land in their liquid form; or, should the con- 

 struction of such reservoirs prove inconvenient, 

 the waste of the liquor ma}' be prevented by rais- 

 ing the dunghill in the manner already stated in 

 our account of (he preparation of firm-yard ma- 

 nure. The application of moisture cannot be con- 

 sidered as a loss; and we have already seen that 

 even thatof waterintrdunirhills is sometimes neces- 

 sary to prevent them from becoming fire-fanged. 



The escape of gaseous matter is caused by the 

 heat created by fermentation; and if we look to the 

 state of a farm-yard, we shall find that, the mo- 

 ment the dung is thrown out, trampled upon, and 

 wetted by the. cattle, that process is commenced, 

 although the temperature, of the heap should be 

 far below 100°. But although the bulk of the ma- 

 nure is thus diminished by the evaporation, yet the 

 effect upon vegetation of the ammonia contained 

 in the vapor has not been conclusively ascertained 

 — nor is there any proof that animal and vegetable 

 substances, while in a state of fermentation, con- 

 tribute to its support; for it appears, from numer- 

 ous experiments, that rank manure, although 

 forcing the early growth of living plants, yet even- 

 tually contributes to their premature decay. Prac- 

 tice has long since decided that it is injurious to 

 turnips, to which crop it is more profusely ap- 

 plied than to any other:* it renders corn crops foul; 



*Mr. Walker, of Mellendean, wbo rents about 2300 

 acres of arable land, has found by the experience of 

 thirty years, that a small quantity of rotten dung is suf- 

 ficient for a crop of turnips — and that all the succeed- 

 ing crops, in the common rotation, are also generally 

 good; but he could never raise a full crop with long; 

 fresli dung, which, from its openness, tends to admit 



Vol. Ill— 83 



and on light and poor land which, containing but 

 little nutriment in the soil, requires all thai can be 

 furnished to it by the manure lor the support of (he 

 present plants, its effect, though olien seen to oc- 

 casion them to push forth with great apparent vi- 

 gor, yet frequently leaves them deficient in grain, 

 and subject to rust. The potato is, indeed, almost 

 the only plant to which it has been found decided- 

 ly friendly; but even that is in many soils known to 

 succeed better with short dung. 



Respecting the effect of u/nfermented dang on 

 Mr. C ke s crops, ti, has been observed, in the 

 treatise to which we have already alluded,* that 

 the statement is only entitled to weight upon the 

 construction either that some of the manure made 

 on the farm that was expended under the old sys- 

 tem is disposable lor some other purpose under the 

 new; or that some expense in fetching manure 

 from distant places, that had used to be incurred, 

 is saved. For, if the assertion 'that his crops have 

 been as good as ever they were, and go nearly 

 twice its far,' mean only that the dung when now 

 expended is nearly twice as much in bulk or 

 weight, and covers the surface of the field more 

 thickly in the same proportion, the benefit is mere- 

 ly illusory, as the crop does not thus appear to be 

 increased; but if the meaning is, 'that twice the 

 surface is immured its effectually with the same 

 quantity of dung' — then, indeed, we should say 

 that the new plan may be fairly considered as en- 

 title 1 to the most serious consideration. 



The same author, indeed, mentions an instance 

 — cited in Dr. Thompson's system of Chemistry — 

 of an experiment, from which it appears that the 

 periods when putrescent manures begin to produce 

 their effects, and the length of time during which 

 they coniinue to operate, are proportioned to the 

 degree of putrefaction under which they are ap- 

 plied. Two pieces, of the same kind of soil, were 

 manured — the one. with a mixture of dung and 

 straw highly putrefied, the other with the same 

 proportions of dung and straw newly mixed, and 

 the straw almost fresh. St was then observed 

 that, during the first year, the plants which grew 

 on the putrefied dung produced a much better 

 crop than the other; but the second year, the 

 ground which had been manured with the fresh 

 dung produced the best crop: the same result took 

 place in the third year, after which both pieces 

 seemed to be equally exhausted. This, however, 

 only showing that the one was productive of the 

 best, crop in the first, and the other in the second 

 year, proves nothing more than an equality of final 

 effect upon the land: upon which it cannot escape 

 reflection, that when the state of the soil does not 

 require progressive improvement, the first crop is 

 generally the main consideration with the farmer; 

 he. naturally, therefore, wishes to place it beyond 

 the reach of those contingencies to which it might 

 be exposed by any deficiency of effective manure. 



drought, instead of affording moisture and nutriment to 

 the roots, while they are young and tender. He is, 

 therefore, at considerable expense in carrying out, 

 turning, and re-turning his dunghills, so as to have the 

 dung in a putrid state when laid upon the land in the 

 month of June. After all he is every year obliged so 

 to manure a part of his turnip land with fresh dung, 

 and irheneerr lint is laid on, the crop is invariably much 

 inferior. — Husbandry of Scotland, vol. i. p. 161. 

 "Treatise on Soils and Manures. Anon, p. 145. 



