ON MANURES. 97 



vesce no longer, and till both the taste and smell of the mixture indicate an 

 excess of alkaline salt. The precipitate that falls down is carbonate of 

 lime : it must be collected on the filter, and dried at a heat below that of 

 redness. 



The remaining fluid must be then boiled for a quarter of an hour, when 

 the magnesia, if any exist, will be throw n down combined with carbonic acid . 



The quantity of lime to be applied to the land must of 

 course be apportioned to the quality of the former, as well as 

 to the nature and the condition of the soil which considera- 

 tions must also be in a great degree governed by the expense. 

 There is perhaps no country where it has been used to such 

 an extent as in the improved parts of Scotland, where it is 

 often carried to the distance of twenty to thirty miles, after 

 having been imported from distant points of the coast, and even 

 from Ireland ; and although it has been laid on at prices vary- 

 ing in proportion to its strength, and the charge of burning, 

 from 6s. to 18s. per chaldron of 36 bushels, besides the cost of 

 carriage, and in quantities according to the nature of the soil, 

 yet the improvement has, in most places of its first application, 

 borne out the charge.* In Ireland, Chief Baron Foster has 

 gone so far as 300 barrels, with manifest good effect. It is in 

 that country, indeed, not uncommonly applied at the rate of 

 400 bushels per imperial acre ; and immense crops of potatoes 

 have been raised by its being laid upon strong old leys, broken 

 up in July or August, and allowed to remain in that state until 

 ploughed again in the spring. It has been laid on some of the 

 moors in Derbyshire to the amount of 1500 bushels. Dr. An- 

 derson says that 'he has himself had experience of it in all 

 proportions, from 100 to above 700 bushels to the acre, upon a 

 great variety of soils ; and that he always found its effect in 

 promoting the fertility of the soil to have been in proportion to 

 the quantity employed, other circumstances being alike ; yet 

 an instance is mentioned, in the Nottingham Report, of twenty 

 chaldrons, or 720 bushels, having been laid upon an acre of 

 cold clay soil, without any benefit whatever. Experiments 

 have also been tried of its application on heavy land, extremely 



*In Scotland it appears that 192 bushels of lime-shells per Scotch acre 

 (equal to 153 per imperial acre) have been applied with success on light sofl 

 land. From 240 to 360 are however generally esteemed proper for different 

 degrees of clay. From thai quantity up to 6(J0 bushels have been laid with 

 good effect on strong land, both arable and under grass ; but it seems gene- 

 rally asrreed, that from 300 to 4^0 bushels are quite sufficient for the greater 

 part of the most fertile districts in that country ; and light soils, whii h 

 require less in the first instance, are said to have been greatly benefited by 

 a frequent repetition, 



9 



