1839] 



FARMERS' REGISTER. 



661 



norant, but experienced practical cultivators of his 

 neighborhood,) was the opinion that our land 

 which was naturally poor could not "hold ma- 

 nure," to any extent or profit, and therefore could 

 not be enriched. For years I heard this opinion 

 .frequently expressed by him, and the evident in- 

 ierence therefrom, that the far greater part of our 

 lands, and ol" the whole country, was doomed to 

 hopeless sterility ; and, as often as heard, I re- 

 jected it as a monstrous agricultural heresy — as 

 treason, indeed, to the authority of Taylor, and of 

 every other author on agriculture whom 1 had 

 read or heartl of. But at last, I was compelled, 

 most reluctantly, to concur in this opinion. 



What was then to be done? I could not bear 

 the idea of pursuing the general system of the 

 country in continuing to lessen the already small 

 productiveness of my fields, by their course of cul- 

 tivation. The whole income, and more, was re- 

 quired tor the most economical support of a then 

 small but fast growing family; and for any in- 

 crease of income or net profit, there w^as no hope, 

 save in the universal approved resort, in all such 

 cases, of emigrating to the rich western wilder- 

 ness. And accordingly such became my intention, 

 fully considered and decided upon, and which was 

 only prevented being carried into effbcl by after 

 occurrences. 



Just before this time Davy's ' Agricultural 

 Chemistry' had been published in this country; 

 and I read it with delight, notwithstanding my 

 then total ignorance of chemical science, and even 

 of chemifal names, except as learned by its peru- 

 sal. There was one passage in this author which 

 seemed to promise to aflTord both light and hope 

 on the point in which disappointment had led me 

 to despair. As an illustration of defects in the 

 chemical constitution of soils, and of the remedies 

 which proper investigation might point out, he ad- 

 duced the fact of a soil "of good apparent texture," 

 which was steril, and seemed incapable of being 

 enriched. The fact which struck so forcibly on my 

 mind was presented in the following concise pas- 

 sage of Lect. iv. "If on washing [for analy- 

 zing] a steril soil, it is found to contain the salt of 

 iron, or any acid matter, it may be ameliorated by 

 the application of quick-lime. A soil of good ap- 

 parent texture from Lincolnshire, was put into my 

 hands by Sir Joseph Banks as remarkable lor stp- 

 rility. On examining it, I found that it contained 

 sulphate of iron ; and I offered the obvious remedy 

 of top-dressing with lime, which converts the sul- 

 phate into a manure." 



Much the greater part of my land, and of all 

 the land of lower Virginia, seemed to me just such 

 as Davy described in this single and peculiar soil, 

 it was certainly of " good apparent texture," that 

 is, it was neither too clayey or too sandy, nor had 

 it any other apparent defect to (brbid its being fer- 

 tile in a very high degree. Yet it was and had al- 

 ways been steril, and, as my experience concur- 

 red with that of my older friend in showing, it 

 could not be either durably or profitably enriched 

 by putrescent manures. Could it be possible that 

 the sulphate of iron (copperas) which Davy found 

 in this soil, and which he evidently spoke of as a 

 rare example of peculiar constitution, could exist 

 in nineteen-twentieths of all the lands of lower 

 Virginial This could scarcely be ; and yet, in 

 despair of finding other causes, I set about search- 

 ing for this one. 



It was not difficult, even for a reader so little in- 

 structed in chemistry, to apply the test for coppe- 

 ras. It was only necessary to let a specimen of 

 the suspected soil remain soaking in pure water, 

 until any copperas, if present, would be dissolved; 

 then to separate the fluid by pouring off and filtra- 

 tion, and then to add to the fluid some of the infii- 

 sion of nut-galls. If copperas had been held 

 in solution, the mixture would produce a true ink, 

 of which the smallest proportion would be made 

 visible in the before perfectly transparent water. 

 But all these first attempts were fruitless, and I 

 was obliged to conclude that the great defect, or 

 impediment to improvement, in most of our soils, 

 was not the presence of the salts of iron. But 

 though not a salt, of which one of the component 

 parts was an acid, might not the poisonous quality 

 be a pure or uncoinblned acid ? This question 

 was raised in my mind, and the readiness produced 

 to suppose the affirmative to be true, from several 

 circumstances. These were, 1st, that certain plants 

 known to contain acid, as sheep-sorrel and pine, 

 preferred these soils, and indeed were almost con- 

 fined to them, and grew there with luxuriance and 

 vigor proportioned to the unfitness of the land for 

 producing cultivated crops. 2nd. That of all the 

 soils supposed to be acid whiah I examined by- 

 chemical tests, not one contained any calcareous 

 earth.* 3rd. That the small proportion of my land, 

 and of all within the range of my observation, 

 which was shelly, and of course calcareous, was 

 entirely free from pine and sorrel, and moreover 

 was as remarkable for great and lasting fertility, 

 as the lands supposed to be acid, for the reverse 

 qualities. Shells, or lime, would necessarily com- 

 bine with, and destroy all the previous properties 

 of any acid placed in contact ; and therefore, if 

 present universally, and always acting as a poison 

 to cultivated plants, it seemed plain enough why 

 the shelly lands were free from this bad quality, 

 and by its absence had been permitted to grow 

 rich, and to continue productive. Every new ob- 

 servation served to add strength to this notion ; 

 and in our tide- water region generally, and even 

 in my own neighborhood, there were plenty of 

 subjects for observation and comparison, both in 

 small shelly and fertile spots, aud a vast extent of 

 poor pine and sorrel-producing lands. Still, I could 

 obtain no direct evidence of the presence of acid, 

 either free or combined, by applying chemical 

 tests to soils, (as was tried in many cases,) nor 

 was there any authority in my oracle, Davy's 

 'Agricultural Chemistry,' nor in any other work 

 which I had read, for supposing vegetable acid to be 

 present in any soil. Though Davy adds to the 

 supposition of the presence of the "salt of iron," 

 "or any acid matter," it is clear from the whole 

 context that he had in view ihe possible and ex- 

 tremely rare presence of a mineral acid (as the 

 sulphuric,) and not vegetable acid, which my views 

 required, and my proofs were afterwards brought 

 to maintain. Sulphuric acid is sometimes found 



* I was not then awaie, of the important and novel 

 fact which I afterwards asceitained and established, and 

 now fully received (with very slight acknowledgement 

 of its source) by the geologists of this country, that 

 almost all the soils on the Atlantic slope of this country, 

 and even including nearly all limestone soils, are also 

 entirely destitute of carbonate of lime, though that in- 

 gredient seems universal in all the good soils of Eng- 

 land, and the continent of Europe. 



