183G] 



P A R M E U S ' REGISTER. 



209 



man with its productions, often suffices to accumu- 

 late upon the soil many inches of protluclive 

 mould. 



1 shall not repeat here the observations whicli I 

 have already made elsewhere upon this soil, the 

 nature and properties of which, appear to have 

 been hitherto so little attended to; however, it is 

 necessary to repeat that in consequence of the ini- 

 permeabilitj' of tjic soil, the plateaux which are 

 ibrmed of it, centain but flnv springs; because, in 

 the first |)lace, the rain water cansiot penetrate in- 

 to the interior to Ibrm and maintain reservoirs to 

 supi)Iy them; but especially, moreover, because 

 the interior waters cannot, but with great dilRcuItj-, 

 escape through the impermeable stratum, to ar- 

 rive at the suriaco. It is probable that in this soil 

 which confines the water. Artesian wells, to give 

 it a passage, would have a better chance of suc- 

 cess than elsewhere. 



These table lands, having in general some de- 

 clivity, enoug'i of rain water rests on the Purtace | 

 to injure vegetation, but not enough to form marsh -■ 

 CF. jNliirshes j.-roceeding irom interior water — 

 ti'om waters below the impermeable stratum, are 

 then also very rare, and can only be met with in 

 this soil, when the impermeable stratum in the 

 bottom of the basins happens to be rnixed in pla- 

 ces witii gravel, which cenders it permeable. 



The small number of marshes which are found 

 in this soil, are placed in the basins of water 

 courses where the imperiTieable stratum has been 

 diluted or modified in its nature ; .they are of small 

 extent, and could be easily drained, because the 

 plateaux themselves have, generally, a very sensi- 

 ble slope. 



These water courses, destined to receive the 

 xvater fi-om rains, and especially fi-om the springs 

 ■of a district, are then also very rare in tliesc lands 

 without springs; and those which are met with, 

 are rapid, and have hollowed out deep valleys; be- 

 cause, the bottom of these valleys tends to come 

 upon the level of the great rivers which flow at the 

 foot of the plateau, and because the plateaux most 

 frequently rise several hundred feet above the le- 

 vel of the rivers, the argilo-siliceous alluvion of 

 these basins has been often entirely carried off.* 



XX. When the argilo-siliceous alluvion is left 

 to itself, the herbage, which elsewhere cov^ers the 

 soil with a close and lasting carpet, comes up upon 

 it weak and thin; and when the surliice is badly 

 dramed, its wetness isliivorable to carex and other 

 species generally of little substance, and even 

 these grow badly and slowly; they are often found 

 accompanied by a variety of moss, which covers 

 the surface, and still more the subsoil when nalced 

 and exposed, with its whitish Ibliagc. When the 

 soil is better drained, heath, broom, (genet) sheep 

 fiorrel^ spuny, (^spergule) fern, the peculiar and ex- 

 clusive vegetables of this soil, take possetssion ol" 

 the surface at the expense of other growths. 

 Sheep are here supported better than on the poor 



* And with it, the beds immediately beneath, which 

 have not offered resistance to the flood — such as the 

 marly beds. The surface soil, or mould, of the bottom 

 of the valley, rests then upon plastic clay — a bed more 

 firm, which is not washed up by, and^its particles sus- 

 pended in water, and which has therefore better re- 

 sisted its force, than tlio beds of other earth that were 

 super-imposed. — Er, 



Yo,.. IV— 27 



herbage of welter soils; other cattle also feed and 



live upon it nearly throughout the summer. The, 

 soil derives remarkable advantages from these ve- 

 getables which it nourishes: man believes that he 

 has a right to complain of them, because they pre- 

 sent obstacles to its cultivation; but these species, 

 Iar<ier than the feeble grasses of turfj leave more 

 dead remainsorlitleron thesoil, andby ahappyfbre^ 

 sight of nature, these remain.sare decomposed with 

 dllTiculty in this inert soil, assume the charac- 

 ter of acid mould. {hu7)ius acide,') and form fiiture 

 resources lor this unfruitful land.* The plants, of 

 the production of which we complain, are then of 

 great benefit to this soil, or rather to us: they have 

 changed the nature of the soil, they have furnished 

 to it the mould (/^i/??^ws) which alone distinguishes 

 it fi'om its arid sub-soil, and have rendered it at 

 last capable of producing the larger vegetables — 

 the trees which cover it in a great many places. 

 But in a few generations, when the previous 

 growth of heath, or of other plants natural to this 

 suH, has not accutnulaled great resources, this suc- 

 ceeding growth of trees is soon exhausted. It 

 happens, then, often in this soil, which receives ibw 

 of the principles of vegetation from the atmos- 

 phere, that the whole growth of woods languishes 

 and disapjiears quickly from the surfiice; then re- 

 appears the alternate cover, or shifl (assolemeni^ 

 of small plants, the producers of acid mould — and 

 the soil, by these means, stores up new powers for 



* Instead of the plants above named, (which, except 

 sorrel, are not indigenous, and perhaps not known 

 here,) let the reader suppose to be substituted the 

 names of our broom grass, the povertj^ (or hen's nest) 

 grass, pine leaves, and whortleberry shrubs, and the des- 

 cription and the general remarks will suit well for our 

 poor ridge lauds, either in woods, or cleared for tillage 

 and again "turned out." These poorest of our natural 

 soils alone, of all in this region, present an accumula- 

 tion of vegetable matter, so great as to be even injuri- 

 ous to cultivated crops — and which, in that respect ex- 

 hibit many points of resemblance to the ])eat soils of 

 Britain, which are unknown in our warmer chme. But 

 it is not merely because the vegetable products above 

 named are slow in decomposing, that they are thus ac- 

 cumulated on our author's "argilo-silicious" lands, or 

 on what we have elsewhere termed "acid soils." The 

 acid ingredient, or property, of such soils, is itself anti- 

 septic, and therefore tending [to preserve from decom- 

 position all vegetable matter in contact. Soils made 

 calcareous, of course lose all acid quality, and the de- 

 composition of these, or any other vegetable remains, 

 proceeds i-apidly. Possibly, this action of calcareous 

 earth is not merely negative — that the effect is not 

 caused merely by its neutralizing and destroying of the 

 antiseptic acid — but that calcareous earth may also pos- 

 sess a positive septic action, which serves to aid and 

 hasten the decomposition of vegetable matter. Many 

 persons, who have not been guided by reasoning, che- 

 mical knowledge or research, have formed this opin- 

 ion, from observing the rapid and entire disappearance 

 of the fallen leaves on the rich limestone forests, com- 

 pared to the great and permanent accumulation on the 

 poor wood lands of Virginia. See Essay on Calcareous 

 Manure!!, 2d Ed. p, 31, and Ch. 8 throughout.— Ed. 



