236 



THE FARMERS' REGISTER. 



curate and scientific investigations of thespi depo- 

 sites,) 1 niustihinlc yourgypeeouseartiiisBtill more 

 variant from our fxreen-sand, tlian Mr. Carter' c!. 

 Ao;ain— Prof. Rogers in his report particularly 

 guards ua against taking any thing (or green- 

 sand which has no shelly matter in it, and more- 

 over i think says the green-sand has never lieen 

 found in this coun:ry vvhen the saddle oyster shell 

 Tvas not present.* Now ] am rather confident I 



" • We readily admit the general inieiionty of the 

 green-sand earth with which we experimented. And 

 it was so, not because there was not plenty of richer, 

 but because we first sou^dit, not for the ereen sand 

 ingredient, but for the greatest quantity of gypsum. 

 But even if poor, enough of the earth was put on to 

 make a very heavy and lich dressing of green- sand. 

 And some of our applications were from the lower and 

 much richer body, (and which also contains shells,) 

 pronounced by Prof Rogers, (for whose inspec- 

 tion the pit was dug.) to contain 60 to 70 per cent, of 

 pure green-sand — and which also produced no lasting 

 effect. The saddle-shaped oyster shell (osiraa sellifor' 

 mis) is found in some of our green-sand ; and at Ever- 

 green, (Piince George,) wherel first discovered the for- 

 mation of green-sand in 1817, and where I afterwards 

 carried Professor Rogers, (in 1835) we gathered the 

 finest and most perfect shells of this kind he had ever 

 seen. Indeed, he then thought this shell to be an un- 

 known species ; and under that mistaken impression, 

 at his request, I obtained for him beautiful drawings of 

 two fine specimens, for the purpose of being engraved, 

 •which were executed by a friend of mine. The 

 same shell is very abundant in the eocene" marl at Cog- 

 gins' Point, which lies over the green-sand, and which 

 green-sand is manifestly changed from what was for- 

 merly the same kind of marl. How the change was 

 produced is a mystery — and we admit, as our friend's 

 comment, afterwards made, intimates, that our specu- 

 lations thereupon are of very little, if any value. 



The green-sand stratum at City Point, like most 

 that we formerly tried at Coggins' Point, does differ 

 in appearance, in constitution, and would ver)' 

 likely difi'er in effect as manure, from that at Newcas- 

 tle, which is the nearest to a pure green-sand of any 

 that has been ])rofitably used there, containing no more 

 than 2 or 2.50 per cent, of carbonate of lime. The 

 City Point stratum contains no shells, but plenty of 

 their empty impressions, and apparently no carbonate 

 of lime. But however different, in some respects, 

 from the Pamunkey beds, (and from our lower stra- 

 tum,) this stratum, like all that we used from, has 

 plenty of green- sand ; therefore, if it be contended 

 (and we are not disposed to deny it,) that this and our 

 own Coggins' Point green-sand earth cannot produce 

 effects as manure equal to those produced by the Pa- 

 munkey and New Jersey earths called by the same 

 name, it will follow necessarily tliat there is some 

 agent of fertilization other than, and superior to, the 

 green-sand itself, and whose presence has not been 

 detected by any scientific investigator. If this be 

 true, it would remove all existing difficulties caused by 

 discordant effects of the (supposed) same agent; for 

 j^ieii Uicre would be no reason why the gf-een-sand 



saw no shell of any kind, particularly of the 

 laiier, at Broad Neck, or at Ciiy Poin'. There 

 are several, and I dare say many of the deposites 

 on this river, or its vicinity, such as you describe 

 in your wiiiinss as gypseous earih, with the clear 

 and distinct impress ol shells, but ail traces of 

 calcareous matter gone. Thai these depositee 

 were or.ce calcareous, I suppose can admit of no 

 duubi^ and, lor aught we know, the green-sand 

 deposiies may have been much more calcareous 

 than ihey are at present ; and may now he un- 

 dergoing the decoinposintr process ; but certain it 

 is to my mind, ihat ihere must have been some 

 other ingredient in the green-sand deposites, than 

 there is in the now gypseous earth deposiies, 

 as a difl'erent result has been produced by the 

 decomposition ; as it would seem liiere is a mark- 

 ed difference heuveen the deposiies Ibund here, 

 one ol' which is called green-sand, and the other 

 gypseous earth. Again, if your rea>oning be 

 correct, id the theory laiely advanced by you, 

 that the sulphate' of" iron, lu percolating through 

 the ditierent sirata of calcareous mailer, has de- 

 composed ihe lime, or ntiher, that ihe sulphuric 

 acid, from iis greater affinity to lime than iron, 

 has produced the more insolutile compound of 

 sulphate of lime, or gypsum, why is it, that we 

 only find the gypsum, in the uppur or overlying 

 stratum of green-sand, and that we still find tlie 

 two lotrether in a se|!;irate state, tlie gypsum in 

 crystals, and (he green-siuid a distinri sutistance, 

 or raiher the crystals of gypsum sometimes as 

 large as a pigeon's egg, intermixed here and 

 (here, ihroui/lmut the straium of green-sand? 

 This green s.uid being weaker, ihal is, containing 

 less gieen-sand, ami a lighter colored earih tlian 

 ihe green-sand ol'ihe lower siraium, and between 

 ihis overlying' siratuin of green-sand, containing 

 the gypsum,- and ihe underlj.iiig siraium of richer 

 green-sand, bu» cnniaining no gypsum, as can be 

 ascertained by analysi.-;, ibere should l>e a vein or 

 siraium of rich green-sand marl, containing 

 someiunes as much as 40 per cent of lime. Il' 

 it decomposed the up[/er, or overlying stratum 

 of whhi WHS once as you suppose a body of 

 marl, or calcareous matier, why dia it noi convert 

 all into gypsum, and how did it pass the inter- 



beds of New Jersey, and of Pamunkey, if having this 

 unknown fertilizing ingredient, should not be every 

 thing that that the report of the state geologist pro- 

 raises for green-sand in general, and yet the James 

 river beds be worth as little as tt)e had inferred, be- 

 cause, though rich enough in green-sand, destitute of 

 that other and unknown ingredient. But if this be 

 so, it takes away the merit as well as the mystery 

 from green-sand, to bestow both on this newly sus- 

 pected and slid unknown agent. 



In conclusion, we agree with our friend and cor- 

 respondent, that almost nothing is yet known on the 

 subject of green-sand ; and we would urge upon all 

 farmers who are able to use it, to do so, in the man- 

 ner best suited to make full experiment, and furnish 

 useful results — and to throw aside as worse than 

 worthless, all that has been yet said of this'raanure 

 in geological reports, and to rely only on what are 

 supposed to be facts, and the results of practical ex-- 

 perience. — Ed. F. E. 



