AND RURAL ECONOMIST. 191 



called animal and vegetable or putrescent manures. They 

 consist oi" decayed and decaying animal and vegetable sub- 

 stances. The other class is denominated fossil manures. 

 The lust mentioned do not properly constitute the food of 

 plants, plthough they enter into the composition of vegeta- 

 bles in miiute quantities. Fossil manures stimulate plants, 

 and cause them to take iheir food faster than thf-.y otherwise 

 would. They are like what medical men call condiments, 

 and answer the same purpose as respects the economy of 

 vegetables which salt, pepper, spices, &c. effect as regards 

 the animal economy. 



The principal fossil manures are lime, gypsum, and marl. 

 We shall make a few observations on each. 



1. Advantages of Lime. Though there are exceptions to 

 the rule, yet, in general, it may be confidently asserted, that, 

 unless where a soil has by nature enough of calcareous 

 matter in its composition for the purposes of vegetation, it 

 can neither be brought into its most fertile states, nor will 

 other manures be so useful as they ought, if lime or some 

 other calcareous earth be not previously applied. By lime 

 spread upon a moory soil, good herbage is produced where 

 nothing but heath and unpalatable grasses grew before. By 

 the same means, grass lands, instead of yielding nothing but 

 bent, and other inferior grasses, have been covered with those 

 of a more valuable description. The utility of lime to tur- 

 nips is so great, that, though in the same field, where no 

 lime had been applied the crop died away, yet in the limed 

 part thf^ turnips flourished with unabated vigor. On the 

 Mendip Imds in Somerset, by the application of lime, the 

 value of land was raised from four shillings to thirty shillings 

 per acre ; and dung, which previous to liming had no sensi- 

 ble effect, operated after its application as on other lands. 

 Macclesfield forest in Cheshire, and vast tracts in the north- 

 ern and more elevated parts of Derbyshire and adjacent dis- 

 tricts, have been astonishingly improved by the same means. 

 The rye lands of Herefordshire in 1636 refused to produce 

 wheat, peas, or vetches ; but since the introduction of lime, 

 they h^ve been so fertilized, as to be successfully applied to 

 the growth of every species of corn. In maiden soils of a 

 tolerable quality, the richest manure will not enable them 

 to bring any crops, but those of oats or rye, to maturity ; 

 whereas, if they receive a sufficient quantity of lime, crops 

 of peas, barley, or wheat, may be raised to advantage. The 

 benefit resulting from the use of lime has been indisputably 



