390 MARLING OF NORFOLK. 



31. The means of ameliorating the texture of chalky soils, are either by 

 the application of clayey and sandy loams, pure clay, or marl." "The 

 ghalk stratum sometimes lies upon a thick vein of black tenacious marl, 

 of a rich quality, which ought to be dug up and mixed with the chalk." 

 Code of Agriculture, p. 19. 



32. Dickson's Farmer's Companion. The author recommends 

 "argillaceous marl" for the improvement of chalky soils; and for 

 sandy soils, "where the calcareous principle is in sufficient abund- 

 ance, argillaceous marl, and clayey loams/' are recommended as 

 manures. 



33. " Chalky loam. The best manure for this soil is clay, or argillaceous 

 marl, if clay cannot be had; because this soil is defective principally in 

 the argillaceous ing'redient," Kirwan on Manures, p. 80. 



The evident intention and effect of the marling recommended in 

 all the three last extracts, is to diminish the proportion of calcare- 

 ous earth in the soil. 



34. In a Traveller's Notes of an agricultural tour in England, 

 in 1811, which is published in the third volume of the Edinburgh 

 Farmers' Magazine, the following passages relate to Mr. Coke's 

 estate, Holkham, and to Norfolk generally. 



" Holkham. The soil here is naturally very poor, being a mixture of 

 sand, chalk, and flint stones, with apparently little mixture of argillaceous 

 earth the sub-soil, chalk or lime-stone everywhere." p. 486. " As the soil 

 of the territory [of Norfolk generally] through which I passed, seems to 

 have a sufficient mixture of calcareous earth naturally, I learn they do not of- 

 ten lime their lands ; but clay marl has been found to have the most bene- 

 ficial consequences on most of the Norfolk soils." p. 487. 



35. "In Norfolk, they seem to value clay more than marl, probably be- 

 cause their sandy soils already contain calcareous parts." Kirwan on Ma- 

 nures, p. 87. 



From this and the preceding quotation it would follow, that the 

 great and celebrated improvements in Norfolk, made by marling, 

 had actually operated to lessen the calcareous proportion of the soil, 

 instead of increasing it. Or, otherwise (as may be deduced from 

 what will follow), if so scientific and diligent an inquirer as Kir- 

 wan was deceived on this very important point, it furnishes addi- 

 tional proof of the impossibility of drawing correct conclusions on 

 this subject from European books when it is left doubtful, whether 

 the most extensive, the most profitable, and the most celebrated 

 improvements by "marling" in Europe, have in fact served to 

 make the soil more or less calcareous. 



If the "clay marl" offered above (4) by Stephens as a fair 

 average, and which contained only 8.40 per cent, of carbonate of 

 lime, is indeed as rich as the "clay marls" or "clays" spoken of 

 in the latter extracts, it would convert the doubt to certainty, that 

 many soils in England were more calcareous than such marl ; and 

 that its application (though truly a calcareous manure), served often 



