1836.] 



FARMERS' REGISTER. 



317 



thickness and value. Such a discovery would not only 

 exhibit a treasure on that precise location, but would 

 indicate its far greater extent. Though the proprietor 

 oC the land first examined might derive the earliest ben- 

 efit, and therefore ought to bear a large proportion 

 of the expense of the experiment, the profitable re- 

 sults would be a thousand times more extensive. Be- 

 sides the land holders through all the adjacent country, 

 the Appomattox navigation interest, and especially the 

 trading interest of the town of Petersburg, would de- 

 rive mostimportant benefits from such a discovery — and 

 therefore the persons connected with such interests may 

 well afford to aid the labors of the Mineralogical Socie- 

 ty, if directed in part to this object.] 



For the t'ai-niers' Register. 



ON THE KFFECTS OP LOXG CONTINUED USE OF 

 CLOVER AND GYPSUi^f, WITHOUT OTHER 

 MEANS OF IMPROVEMENT. 



Mr. Peyton, in his communication to the Regis- 

 ter, lor July, imputes to me error in relation to liie 

 long and continued application ofgypsum, unaided 

 by other manures!. Having observed Irom several 

 papers in the Register, ihat the writers seemed to 

 consider gypsum a means of permanent improve- 

 ment, I thought proper to state what I apprehend- 

 ed to be the effect on my own lands. I should be 

 well pleased to find I had been mistaken. 



Chemistry applied to agriculture, has been among 

 tlie improvements of the age, and though men of 

 science, by analysis, have discovered many of the 

 elements ol matter. 1 think much has escaped their 

 searching enquiries, 1 am always willing to pay 

 tribute where tribute is due, and concur with JMr. 

 Peyton, that the world is largely indebted to Sir 

 Humphry Davy, and the Count Chaptal, for their 

 labors and discoveries; but I have never been sa- 

 tisfied with the theory of Knight, though sanctioned 

 by the Count, that in the districts in England, 

 where the application of gypsum has been found 

 to be inert, that it resulted from a superabundance 

 contained naturally in the soil. If this theory was 

 right, I should suppose that clover, and other plants 

 apposite to gypsum, would flourish by its power 

 eontained in the soil. From one to two bush- 

 els of gypsum has been supposed, by those who 

 have been well practiced in its etiects, to be 

 as efficacious a,s any additional quantity, but I have 

 never heard that an excess, however great, has 

 proved deleterious. In this respect it seems to as- 

 similate to marl. Mr. Rutfin, in his Essay on Cal- 

 careous Manures, states, as the result of experience, 

 " that clover, red and white, will flourish on spots 

 most injured for grain crops, by marling too heavi- 

 ly." Count Chaptal, who seems to have added 

 practical experience to his theoretical speculations, 

 asserts that gypsum acts as a condiment, or spice, 

 to tlie digestive organs of plants. If his theory be 

 true, and we receive what general expejience 

 seems to have established, that a redundancy of 

 gypsum is in no way injurious to clover, when arti- 

 ficially applied, it may be reasonably inferred, that 

 it either rejects, or throws ofl[' the superfluity. Ana- 

 logy to animal economy, seems to ti;ivor this posi- 

 tion. Medicine is useful in sickness, and Ibod in- 

 dispensible in health; but the reception of too large 

 a quantity, instead of imparting convalescence in 



the one case, and vigor in the other, will lead to dis- 

 ease, and sometimes death; and it the organs of 

 the j)lant be capable of perlbrming this salutary 

 operation, when an excess of gypsum is artificial- 

 ly applied, I can see no cause why she should not 

 exercise the same function where an excess of the 

 gj'psum exists naturally in the soil. 



Lands on the Eastern Shore of Maryland, which 

 do not profit by the api)lication of gypsum, as iitr 

 as my observation extends, in their natural state, 

 are least favorable to the growth of clover, red or 

 wdiite, or to Indian corn. They are stiflj white, 

 clayey lands. When highly improved by putres- 

 cent manures, for a short time they will produce 

 rich crops of red clover, but it disappears after the 

 first cultivation, and is rarely succeeded by a 

 growth of white; and a rich dressing by putres- 

 cent manure does not seem to bring into action any 

 property which was dormant in the soil. If, as 

 Mr. Ruflin alledges, a dressing of putrescent ma- 

 nures will restore to healthy action lands which 

 have been surcharged with marl, the same result 

 might be expected, wdien they hold a surfeit of 

 gypsum naturally existing in the soil or artificially 

 applied. If the reasons given by Sir Humphry 

 Davy for the inaction of gypsum, on soils in Eng- 

 land, apply to those of America, I doubt its cor- 

 rectness: nor have I entire confidence in the cor- 

 rectness of Count Chaptal's theory in relation to 

 the action ofgypsum on plants.* Tlie speculation 

 is ingenious, but I think the mystery still remains 

 unresolved. In stating these causes of doubts, I 

 hope to escape the charge of presumption. I sa}^, 

 in truth, that I am an unlearned man. My pur- 

 suits have led me into paths wide of the delightful 

 science of natural philosophy. My opinions are 

 the results of my own crude reflections and a very 

 limited experience. 



I find, by referring to my essay in your No. for 

 May, that I said, as I intended to do, that though 

 my crops of wheat were greatly diminished, that 

 corn grew well and clover flourished; and as Mr. 

 Peyton suggests, by a more intimate knowledge 

 of ray course of cultivation he might be able to as- 

 certain the cause of failure, I will make a state- 

 ment somewhat more minute. My farm lies on a 

 salt water river: the soil friable, with a red clay 

 bottom. Under a high state of improvement, it 

 will produce from twent\' to thirty bushels of wheat, 

 and from forty to fifty of Indian corn to the acre. 

 This I have ascertained from small portions which 



*No theor}^ of the mode of operation of gypsum, as 

 manure, that has yet been published, is at all satisfacto- 

 ry. But even though the action ofgypsum may continue 

 to be inexplicable, its inaction may be plausibly ac- 

 counted for under certain and various circumstances. 

 As it is well known that only a limited quantity can act 

 as manure, and that any excess above that quantity 

 would be totally inoperative, Davy's explanation of its 

 inertness, on soils known already to possess gj'psum as 

 a natural ingredient, is amply satisfactory. On the 

 other hand, our poorest lands, which are totally de- 

 void both of calcareous earth and gypsum, are as little 

 benefited by the latter. On the supposition of oxalic 

 acid being present in such soils, a reason for gypsum 

 not acting is equally clear, as we have explained at 

 length elsewhere. See Essay on Cal. Man. pp. 92, 93, 

 2nd Ed. Ed. Far Reg. 



