LIME IN COMPOST HEAPS. 267 



in use in Normandy, that the longer the compost heaps were kept 

 before being carried out as manure, and the more often they were 

 cut down, the parts mixed, and again heaped, the richer and more 

 efficient would be the manure. Now this seemed scarcely less 

 strange than the general result. For, after as many mixings and 

 turnings of the mass as would serve for thoroughly separating each 

 ingredient, and mingling the whole together, with enough of time 

 for the combining chemical action between the different elements, 

 there appeared no reason why the compound mass could gain more 

 in richness, and the putrescent parts would probably lose, by con- 

 tinued exposure and further decomposition. But even if such 

 were the case as to the original materials of the compost, yet doubt- 

 less the formation of nitrates continued, and their quantity was in- 

 creased with every new exposure of surface, and through the whole 

 course of time. 



Under these impressions, I now deem much more valuable and 

 worthy of imitation the very light limings, in compost, of La 

 Sarthe ; and as especially suitable when a farm throughout has 

 once been well calxed, and it is yet too soon to repeat the applica- 

 tion in any considerable quantity. This plan, of very light lim- 

 ings, in compost, offers ample remuneration for using lime as ma- 

 nure in localities so distant from the source of supply, that the 

 carriage of enough for ordinary dressings might be more expensive 

 than profitable.* 



III. Improving tJie health, and promoting tlie vigour and perfec- 

 tion of plants. 



The beneficial effects of calxing are not to be measured by the 

 mere increase of the bulk or quantity of products, and still less in 

 comparison with crops on similar land not yet calxed, in seasons 

 when both lands, according to their different qualities, yield well. 

 The addition of calcareous earth, when before greatly deficient, serves 

 to so improve the fitness of the land for vegetable production, that 



* It may be of use to some readers, who have no access to either of the 

 works above referred to, to state here concisely the mode of making this 

 compost in Normandy, and also in Belgium, as reported by Puvis. He 

 says: There is first made a bed of earth, mould, or turf [peat], of a 

 foot or thereabout in thickness. The lumps are chopped down, and then 

 is spread over a layer of unslaked lime, of a hectolitre [2- bushels] for 

 every 20 cubic feet of earth. Upon this lime is to be placed another layer 

 of earth [of like kind], equal in thickness to the first, then a second layer 

 of lime ; and then the heap is finished by a third layer of earth." As soon, 

 as the lime is fully slaked, by the moisture of the earth, "the heap is cut 

 down, and well mixed ; and this operation is repeated afterwards, before 

 using the manure, which is postponed as long as possible, because the 

 power of the effect on the soil is increased with the age of the compost, 

 and especially if it has been made with earth containing much vegetable 

 mould " 



