302 



FARMERS' REGISTER. 



tirely of clay and lime, in various proportions, but 

 areneraily about one-third of lime and two-t birds 

 of clay.* IMarsh-miid is valuable because it con- 

 tains bolh of these, although the lime is in small 

 proportions. Add lime or dead shells to marsh- 

 mud, and you make a very complete marl. Clay 

 is found in vast quantities near all our sandy lands: 

 if this alone were spread and intermixed, it would 

 stiffen the soil, and enable it to retain the moisture 

 which now passes rapidly through it and does but 

 little good lo the crop. LpX snme lime be added 

 to this clay and you have marl. So also with the 

 mud from ponds, creeks, swamps, bays and 

 branches, that run in or near to every field. If 

 lime be added to these last, you not only have 

 marl but decayed vegetable manure also. 



Mr. RtjfTin says, ihat two lo three hundred 

 bushels of marl to (he acre, thrown hrnnd-cast, is 

 generally the best proportion. I obtained very 

 satisfactory results from sixty and nine'y bushels 

 to the acre when put into the hills with the corn ; 

 the produce Vv'ould probably have been greater, if 

 I had increased the proportion of marl. 



I think that Mr. Ruffin has fallen into one error, 

 f om his not beinff sufRcienily acquainted with 

 chemistry, an unfortunate error, as it excites 

 doubts of all the benefits ascribed by him to lime. 

 He fifives the analysis of some lands which he 

 says contain no lime whatever, and yet they are 

 very productive and rich. If Mr. Ruffin would 

 add with his own hands any quantity of sulphate 

 of lime, or of oxalate of lime, to this very soil, the 

 result would be the same, with the tests that he 

 u-ed. His tests cannot detect these preparations 

 of lime, and yet they are believed to be the most 

 powerful forms in which lime can be applied to 

 vegetation. The effects of sulphate of lime, gyp- 

 sum, or plaster of Paris, are well knov;n, and it 

 exists in many soils by a process of nature. So, 

 no doubt, does the oxalate of lime, formed by the 

 decomposition of oxalis (sorrels.) rumex (docks,) 

 and other weeds crrowin<T luxuriantly on such 

 lands, the acid of which unites to the lime where- 

 ver found, and then it can only be discovered after 

 exposure to the heat. 



Your moBt obedienr servant, 



.Tos. Johnson. 

 Charleston, ^pril 2d, 1840. 



1 have reason to believe, that calcareous ma- 

 nures are this year used pretty extensively by five 

 or six planters, and tried as experiments by as 

 many more. J. J. 



[We rejoice to learn from the above article, that 

 marl has been employed by the planters of South 

 Carolina, even to the slight extent stated. We 

 have formerly several times referred to the rich 

 resources of that slate for its agricultural im- 

 provement ; and, even to the last time, express- 

 ed regret that they were entirely neglected. But 

 if even " five or six planters " are this year mak- 

 ins proper applicatione of marl in South Carolina, 



* Not so as to the marls of lower Virginia, which it 

 is presumed are meant to be included in the above re- 

 mark. Very few of these contain much clay ; and 

 their earth, other than carbonate of lime, is mostly of 

 silicious sand. — Ed. F. R. 



it must lead to extensive aiid general improvement 

 by that means. 



The large proportion of [carbonate of] magne- 

 sia which Dv. Johnson reports as so generally 

 present in the marls of South Carolina, is a re- 

 markable and interesting fact, which requires at- 

 tention and full investigation. Writers of reputa- 

 tion have maintained that magnesia is hurtful to 

 land. We have no experience on that head, but 

 do not concur in that opinion. 



Next, as to matters personal : If the writer of 

 the above article had merely charged, in general 

 terms, the author of the 'Essay on Calcareous 

 Manures,' as "not being sufficiently acquainted 

 with chemistry," no reply would have been made, 

 because thai fact has been fully and expressly ad- 

 mitted by himself in the work in question. But 

 as it is charged that a particular " error " is the 

 effect of that want of sufficient knowledge, and 

 that that error is so important as to " excite doubts 

 of all the benefits imputed by the author to lime," 

 it is proper to say, that the error charged has no 

 existence; and that Dr. Johnson either has not 

 read, or has not understood the reasoning of the 

 work, which he speaks of so approvingly in other 

 respects. The author did indeed state that very 

 many of the most fertile soils, and indeed almost 

 all soils, rich and poor, of all the great Atlantic 

 slope of the United States, were totally destitute of 

 carbonate of lime; and he still maintains this im- 

 portant proposition, which he was the first to an- 

 nounce. But so far from asserting the absence 

 of lime, in all or any other combinations, directly 

 the reverse was maintained; and (he ground thus 

 assumed forms an important and essential part of 

 the theory of the causes of fertility or barrenness 

 of soils. To establish this general existence of 

 lime in some other state of combination than the 

 carbonate in all rich soils is the main object of the 

 reasoning and prools in the chapter on " neutral 

 and acid soils," (page 22, second edition,) and the 

 truth there established is relied on to sustain the 

 subsequent reasoning throughout, and is particu- 

 larly referred to, in several cases, for explanation 

 of particular and remarkable effects. Two of 

 them, now remembered, are in the chapter on the 

 "permanency of calcareous manures" (p. 58,) 

 and the explanation of the inaction of gypsum on 

 acid (or ordinary poor natural) soils, (p. 92.) — Ed. 

 F. R.] 



VALUE OF ASHES. 



From the Cultivator, 

 il/essrs. Gaylord and Tucker— From observa- 

 tion and actual experiment, I have come to the 

 conclusion that leached ashes are worth at least 

 six cents per bushel, to incorporate into a gravelly 



