On Manures. 229 



the agriculture of the latter county has been improved. It 

 is applied in various proportions, from one-half to one-sixth 

 of a ton per statute acre, the quantity being regulated by 

 the quality and condition of the land, by the nature of the 

 crop, aad by the means of the farmer. Mr Curwen ascer- 

 tained, that five hundred weight of rape-cake, mixed with 

 two tons of dung, will manure an acre for turnips (* 55 ). 



It lias been found in Flanders, that powdered rape-cake, 

 strewed over the surface of the ground, destroys the gryllus 

 talpa, so injurious in wet-soils ; and every insect of the same 

 species, may be destroyed by the same means. 



Such is the quantity of this manure used in the Nether- 

 lands, that a farmer, who only cultivates 75 English acres, 

 purchases at the rate of 5000 rape-cakes, and 3300 cakes 

 from poppy-seed, for manure, which cost him nearly L. 60 

 per annum ( 25<s ). 



The quality of the dung produced in a straw yard, is 

 wonderfully enriched, by giving the cattle a portion of oil 

 cake. A farmer in Cambridgeshire actually gave his cattle 

 cake, for that purpose alone, when he knew that the price 

 of beef would yield him no remuneration for it; and so con- 

 vinced are the farmers upon the light soils in Surrey, of its 

 efficacy, that they have been known to give a field of turnips 

 to a sheep jobber, upon the sole condition, that the sheep 

 were to have a certain quantity of cake, to be eaten upon the 

 field, along with the turnips. 



7. Tanners' Bark. Mere woody fibre, like tanners' bark, 

 requires fermentation to render it nutritive to plants ( a57 ). 

 It is sometimes mixed with lime, but a compost with dung, 

 is more likely to be useful in rendering this substance fer- 

 tilizing; or it may be mixed with a clayey soil, to render it 

 more tender and friable. It will not bear a distant convey- 

 ance. 



8. Vegetables ploughed in. The propriety of this system 

 is much disputed. It was practised by the ancients, and is 

 still said to answer well in warm climates ; and in the warm 

 seasons of cold climates. Several successful experiments 

 with ploughing in vetches, the tops of turnips, and the 

 stalks of potatoes, have been detailed by an intelligent 

 agriculturist in Ireland ( s58 ). But after being tried for se- 

 veral years in Lincolnshire, with buck-wheat, it was ulti- 

 mately given up as doing no good( a59 ); and the general 

 opinion is, that more benefit is derived from green crops, 

 when consumed by stock, and converted into dung, than 

 when ploughed in, without any mixture of that animal mat- 



