MISTAKEN IDEAS OP MARL. 421 



tico and results, it will be necessary to recur to some other con- 

 nected branches of the subject. The reader will pardon the apparent 

 digression. 



So well established and general has the opinion now become that 

 this marl is a manure, and a most valuable one, that it may seem 

 strange that I should have only arrived at such an opinion indirectly, 

 by the train of reasoning indicated above. There were hundreds of 

 persons who afterwards said, " Oh ! / never doubted that marl was 

 a good manure ;" but not one of whom had been induced before me 

 to try its operation. But passing by these postponing believers, 

 and 'all others who confessedly never attached any value to this 

 great deposit, it may require explanation why I had not learned its 

 value from English works which treat so extensively on marl, even 

 though I had then had access to but few of them. It was precisely 

 because I had read attentively some of the English accounts of 

 marl that I was deterred from using our marl, which agreed with 

 it (apparently) in nothing but name. Struck with the importance 

 attached to marl in England, I had earnestly desired to find it, and 

 had searched for it in vain, years before the early beginning of my 

 farming. The name induced a close examination of what was 

 called marl here; but the "soapy feel/' the absence of grit, the 

 crumbling and melting of lumps in water, &c., which were the most 

 distinguishing characteristics of the marl of the English writers, 

 were in vain looked for in our shell beds of which the earth was 

 generally sandy, never " soapy," and of which the lumps were often 

 of almost stony hardness, and if not, at least showed nothing of the 

 melting disposition of the English marls. I had before this found, 

 however, in the American edition of the " Edinburgh Encyclopae- 

 dia," more modern and correct views of marl, and had thereby 

 learned to prize calcareous matter in general as an ingredient of 

 soil, whether natural or artificial. But even admitting that the 

 shelly portion of our marl would slowly decompose, and gradually 

 furnish some manure to the soil, still it seemed that there was little 

 prospect of its operating as the English marl, of such very different 

 texture and qualities. I then supposed that the shells which had 

 resisted decomposition, even where exposed on the surface of the 

 beds, for centuries, would be as slow to dissolve, and to act as ma- 

 nure, if laid upon the fields. Still, notwithstanding these grounds 

 of objection, the general idea of the value of calcareous manures 

 would have induced me earlier to try fossil shells, but for being 

 deterred therefrom by the only actual facts then known of the use. 

 When speaking of my thought of trying marl to my friend Mr. 

 Thomas Cocke, he told me that it was not worth the trouble ; that 

 he (attracted merely by the name of "marl"), had made several 

 small applications, in 1803, on soils of different kinds, and that he 

 had found almost no visible benefit ; and he had attached so little 

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