102 



THE SOUTHERN PLANTER. 



point, by extracting and condensing his remarks 

 as they are scattered through the lecture : 



" On clay lands more lime is necessary than 

 on light and sandy soils. This may be partly 

 ascribed to the physical effect of the lime in 

 opening and loosening the stiff clay — but inde- 

 pendent of this action the particles of lime are 

 liable to be coated over and enveloped by the 

 fine clay, and thus shut out from the access of 

 the air. These particles, therefore, must be 

 more numerous in such a soil if as many of 

 them are to be exposed to the air as in lighter 

 land, through which the atmospheric air con- 

 tinually permeates. 



" On wet and marshy soils, a larger applica- 

 tion still may be made with safety, and partly 

 for the same reason. 



" The moisture surrounding the lime shuts 

 out the air, without the ready access of which 

 lime cannot perform its important functions. — 

 The same moisture tends to carry down the 

 lime and lodge it more speedily in the subsoil. 

 The continued evaporation also keeps such soils 

 too cold to allow the chemical changes, which 

 lime in favorable circumstances produces, to pro- 

 ceed with the requisite degree of rapidity. The 

 soluble compounds which are formed as the con- 

 sequence of these changes are, in wet and 

 marshy soils, dissolved by the moisture, and so 

 diluted as to enter in smaller quantity into the 

 roots of plants. And lastly, in certain cases, 

 new compounds of the lime with the earthy 

 and stony matters of the soil are formed, which 

 may either harden into visible lumps of mortar 

 and cement, or into smaller particles of indurated 

 matter, in which the lime is no longer in such a 

 state as to be able to act in an equal degree as 

 an improver of the soil. 



" In cold and wet clays, in which all these 

 evil conditions occasionally meet, it is not sur- 

 prising, therefore, that large doses of lime should 

 sometimes have been added without producing 

 any sensible benefit whatever. 



"Again, when the soil is also rich in vegeta- 

 ble matter, lime may be still more abundantly 

 applied. Thus, when a field is at once wet or 

 marshy, and full of vegetable matter, as our 

 peat bogs are, lime may be laid on more un- 

 sparingly than under any other circumstances. 

 For in this case, besides the action of the ex- 

 cess of water, as above explained, the vegetable 

 matter combines with and masks the ordinary 

 action of a considerable quantity of the lime. — 

 By this combination, no part of the ultimate in- 

 fluence of the whole lime upon the soil is ne- 

 cessarily lost ; in most cases the immediate effect 

 only is lessened, which the same quantity ap- 

 plied to other soils would have been seen to pro- 

 duce. In favorable circumstances its action is 

 retarded and prolonged, the compounds it forms 



with the vegetable matter decomposing slowly, 

 and, therefore, remaining long in the soil. 



" Not only the natural depth of the soil, as 

 already stated, but also the depth to which it is 

 usually ploughed, and to which it is customary 

 to bury the lime, will materially affect the quan- 

 tity which can be safely applied. A dose of 

 lime which would materially injure a soil into 

 which the plough rarely descends beyond two 

 or three inches, might be too small an applica- 

 tion where six or eight inches are usually turned 

 over by the plough. When new soil, also, is to 

 be brought up, which may be supposed to con- 

 tain no lime, or in which noxious substances 

 are present, a heavier dose of lime must neces- 

 sarily be laid upon the land. 



"Such are the circumstances in which large 

 applications of lime may be usefully applied to 

 the land. In soils of an opposite character not 

 only will smaller quantities of lime produce an 

 equally beneficial effect, but serious injury would 

 often be inflicted by spreading it too lavishly 

 upon your fields. 



" The more dry and shallow the soil, the 

 more light and sandy, the less abundant in ve- 

 getable matter, the more naturally mild its lo- 

 cality, and the drier and warmer the climate in 

 j which it is situated — the less the quantity of 

 s lime which the prudent farmer will venture to 

 j mix with it. It is to the neglect of these na- 

 tural indications that the exhaustion and barren- 

 i ness that have occasionally followed the appli- 

 cation of lime are to be ascribed. It is only in 

 rare cases, such as the presence of much noxious 

 mineral matter in the soil, that these indications 

 can be safely neglected. 



"But a difference of opinion also prevails 

 i amongst practical men, as to whether that quan- 

 I tity of lime which land of a given kind may 

 | require ought to be applied in large doses at 

 I long intervals, or in small quantities frequently 

 ! repeated. The indications of theory in reference 

 j to this point are clear and simple. 

 I "A certain proportion of lime is indispensable 

 in our climate to the production of the greatest 

 possible fertility. Let us suppose a soil to be 

 wholly destitute of lime — the first step of the 

 j improver would be to add to it this indispensable 

 proportion. This w r ould necessarily be a large 

 quantity, and, therefore, to land limed for the first 

 time theory indicates the propriety of adding a large 

 dose. 



11 Every year, however, a certain variable pro- 

 portion of the lime is removed from the soil by 

 natural causes. The effect of this removal in 

 a few years becomes sensibly apparent in the 

 diminished productiveness of the land. After 

 the lapse of five or six years, during which it 

 has been gradually mixing with the soil, the 

 beneficial effects of the lime are generally the 

 most striking — after this they gradually lessen, 

 till at the end of a longer or shorter period, the 



