422 



FARMERS' REGISTER 



[No. 7 



Society, Vol. II 207, having observed the fertility 

 of the lands in the neighborhood of Catana in Si- 

 cily, which abound in volcanic matter, was led to 

 infer the vegetative virtue of sulphur. He caused 

 brimstone to be pounded and sifted, and mixed 

 with ashes, to render the sowing easy. "The ef- 

 fect was surprising on lucerne and clover, but little 

 perceptible on wheat and natural grass." The 

 experience of Judge Peters seems to afford some 

 confirmation of this statement. If sulphur is so 

 efficacious, the difficulty expressed by you, of ac- 

 counting for the. great efficacy of the gypseous 

 earth on the supposition that gypsum was the only 

 active principle of that substance, is at once re- 

 moved. 



5th. This theory receives some confirmation 

 from the fact that these beds are invariably wet 

 near the surface, where the water may be suppo- 

 sed to be formed by the union of the hydrogen 

 of the sulphuretted hydrogen, with the oxygen of 

 the air; and the shells arc decomposed only to the 

 depth of a few feet below the surface, to which 

 depth the sulphuric acid in solution may be sup- 

 posed to percolate. 



6th. The blue or green color of this deposite is 

 a circumstance in some measure confirmatory of 

 the theory. "It is a property of sulphuric acid to 

 dissolve a small portion of sulphur, whereby it 

 acquires a blue, o- r een, or brown tint." ( Turner's 

 Chem. 1SS.) The color of the marl may be oc- 

 casioned by a combination of a small portion of 

 the sulphur, deposited by the sulphuretted hydro- 

 gen, with a portion of the sulphuric acid supposed 

 to enter into its composition. This may also pos- 

 sibly account for the fact of the change of the co- 

 lor of marl from yellow to blue, produced by put- 

 ting it in a farm-yard, as reported in a note 'to the 

 2nd edition of the Essay on Calcareous Manures, 

 page GO. The urine of the horses, &c may be 

 supposed to be the ao-ent— for independently of the 

 sulphuric acid which it contains in combination 

 with soda and potash, it is supposed also to con- 

 tain some acid in a free state, and also a minute 

 portion of sulphur. 



The result of this theory, if if be correct, is that 

 the gunpowder marl of New Jersey, and the sim- 

 ilar formations in Virginia, do not owe their effica- 

 cy entirely to the green sand, as has been suppo- 

 sed, but mainly to sulphur and gypsum, two pow- 

 erful fertilizing agents. And as a consequence, 

 most important to the agriculture of eastern Vir- 

 ginia, that the upper strata of our marl beds, con- 

 taining the impression of shells, and heretofore 

 regarded as comparatively worthless, are the most 

 valuable portions of these deposites. 



The correciness of this theory might be with 

 certainty tested, or at least the truth of the proof 

 adduced in support of it, by chemical analysis. 

 And it may be asked why is this not done? " To 

 make a perfect analysis of a compound substance, 

 such as the green sand or marl, is a task requiring 

 a degree of care, patience, and scientific know- 

 ledge, to which few persons can lay claim. It is 

 no difficult matter to "analyze a specimen of marl, 

 so as to ascertain the quantity of carbonate of 

 lime contained in it; but this operation falls far 

 short of a complete analysis, or resolution of any 

 compound substance into its elements. All the 

 analyses of marl, the results of which I have yet 

 seen, have been confined principally to this object. 



A complete analysis of this substance is much to 

 be desired. 



In offering these crude conjectures to your read- 

 ers, I beg to be understood as claiming for them 

 but a small degree of confidence. I make no pre- 

 tensions to the character of a chemist — all the 

 knowledge 1 possess of the science having been 

 derived from attending at a very early period, the 

 usual collegiate course, and from such subsequent 

 reading and reflection on the subject, as its inti- 

 mate connexion with agriculture has induced me 

 to bestow upon it. If this communication should 

 have the effect of engaging for this interesting 

 subject the attention of other gentlemen, whose 

 greater knowledge and better opportunities for in- 

 vestigation, will enable them to afford more satis- 

 factory information to the public, all that I desire 

 will be accomplished. That the physical sciences 

 are yet in their infancy is most obvious; and what 

 we now vainly call philosophy, is but the alpha- 

 bet of that universal knowledge, which, in the 

 course of future ages, will be developed, by the 

 energy and intelligence of man. Yet enough is 

 already known by those who have studied nature, 

 as far as her wonderful and mysterious operations 

 have yet been explored, to enable them to impart 

 to others much useful and interesting information. 

 The cause of science, and the interests of agricul- 

 ture and the arts, require that it should not be with- 

 held. 



WII.LOUGIIP.Y NEWTON. 



Linden, (Westmoreland,} Aug. 12, 1835. 



[It is gratifying that the inquiring mind of our cor- 

 respondent has been directed to an important and in- 

 teresting subject, which lias in no respect been yet 

 made clear — and which still needs better explanation 

 than is furnished by the foregoing theory. Itis hoped 

 that others will aid in the investigation, and that satis- 

 factory and valuable conclusions may be thereby reach- 

 ed. Having elsewhere given our early opinions at 

 large concerning "gypseous earth," in the article re- 

 ferred to above, we shall now merely mention very 

 concisely, a few facts, or deductions from facts, which 

 seem to bear on Mr. Newton's reasoning. 



The shining particles which Prof. Rogers called 

 mica, and which are generally, if not universally seen 

 in this earth, are not selcnite. This would sufficiently 

 appear from the correctness with which that gentleman 

 would certainly apply the names of such very differ- 

 ent substances presented in specimens under his ex- 

 amination. Long before we had ever heard of "green 

 sand," or had seen a specimen of "Jersey marl," or 

 had met with any pei-son who was better acquainted 

 with it, we maintained the identity of the latter sub- 

 stance with the "gypseous earth" of Virginia, and at- 

 tributed the value of both (when there was any value,) 

 solely to, gypsum. But gratifying as it would have 

 been to have had the proof which the universal pre- 

 sence of gypsum (or selenite) would have afforded, 

 the rough modes of chemical investigation used sel- 

 dom found that substance, which could not have been 

 the case if it composed all the shining particles con- 

 tained. 



In the body of gypseous earth af Berkeley, sul- 



