212 SINKING OF LIME. 



the upper, loose, and fertile, and the lower, more or less impervious 

 and unproductive soil. In arable lands, the action of the plough 

 counteracts this tendency in some measure, bringing up the lime 

 again from beneath, and keeping it mixed with the surface mould. 

 Yet through ploughed land it sinks at length, especially where the 

 ploughing is shallow ; and even the industry of the gardener can 

 scarcely prevent it from descending beyond the reach of his spade." 

 (p. 397.) 



Such results, frequent as they doubtless are in England, are cer- 

 tainly very rare, and of no material disadvantage in this country. 

 Indeed, until very lately (in 1851), I had never heard of any such 

 case. But then I learned from Mr. John A. Selden, that he has 

 observed this effect on his highly improved and well limed farm, 

 Westover. I had before inferred that this sinking of lime, in its 

 separate and pure state, could not occur except where it had been 

 applied in excess as must be generally done in the usual heavy 

 applications in England; and that it was only the excess of lime, 

 which the soil did not then need, and with which, therefore, the 

 organic matter could not combine, that could thus continue sepa- 

 rate, and sink through the open soil. If such combination had 

 taken place (as I suppose of a barely sufficient application), of all 

 the lime with the organic matter, and of both with the other earthy 

 parts of the soil, then the lime could not separate from its combi- 

 nation, and of course could not sink alone. Neither could it carry 

 with it the other matters in combination. This sinking, it seems, 

 does not occur with marl, or other " impure calcareous manures," 

 but with the finely powdered burnt lime only. When breaking up 

 land for a second cultivation subsequent to its having been marled, 

 I have often seen the plough bring up marl, unchanged in appear- 

 ance, from the bottom of the furrow. But this had been before 

 turned under (when first spread) to that depth, and had not been 

 reached and intermixed by the after tillage. Caustic lime is applied 

 in England very heavily often as much as 300 bushels, or more, 

 unslaked, to the acre and repeated at intervals of about twenty 

 years. And these, or lighter dressings, must often occur on soils 

 before calcareous, either naturally, or made so by previous liming. 

 In either of these cases, I would deem any addition of lime, how- 

 ever small, to be in excess, for the time j and of course such ex- 

 cessive quantity would remain uncombined, and therefore subject 

 to waste. In this country, all liming has been given in compara- 

 tively light dressings, and very rarely, if ever, to a calcareous soil ; 

 and therefore it was rare that any portion of the lime was in 

 excess, and consequently remained separate and uncombined. And 

 it is because of these very different conditions that the sinking of 

 lime, an effect so common and notorious in England, should be so 



