38 



FARMERS' REGISTER. 



[No. 1. 



creek. The high banks on the inlet of this creek ex- 

 hibit thick buds of good marl, (No. 24,) the shells of 

 which are imbedded in a stiff clay. The bed at one lo- 

 cality — on the farm of Mr. William Pratt — is covered 

 by a thick stratum of a very plastic chocolate-colored 

 clay, which itself might serve as a useful amendment 

 to the thin soils of the surrounding country. 



"J3ut perhaps the most valuable beds of shell-marl 

 in this part of Talbot county, inasmuch as they may 

 be made extensively available to the public demands 

 for the article, are those which were fully described in 

 the preceding report. They occur three miles below 

 Dover bridge, forming the high bank from fifteen to 

 twenty feet above tide, being one compact mass of fos- 

 sil shells, and extending nearly a mile along the river, 

 on the farms of the late Col. Smyth and Mr. Atkinson. 

 These beds are in contiguous strata, apparently succes- 

 sive, and consist of vast accumulations, principally, in 

 the asscending order, of oyster shells, succeeded by 

 clam shells intermixed with other marine shells, scal- 

 lop, clam and scallop, and uppermost principally of 

 scallop. Endeavor was made to bring these beds into 

 notice, witli a view of enlisting them into the public 

 service, by giving to their proprietors what was deem- 

 ed proper directions for extracting the material, and 

 salutary advice as to a just estimate of its value, in or- 

 der to secure a constant and permanent disposal of it. 

 The subject is now in progress of experiment. South 

 of these banks on the Choptank, no other deposite of 

 marl is known to occur." p. 19. 



Several of the foregoing passages, in addition 

 to many other incidental remarks through the re- 

 port, exhibit in many of the land owners a decree 

 of neglect and ignorance of the value of their bo- 

 dies of jbssil shells, which is the more strange and 

 unaccountable, when it is considered that the first 

 known profitable use of this manure was made 

 thirty years ago in part of this region of coun- 

 try, (by Mr. Singleton) and that the example had 

 been successfully followed on many other farms in 

 Talbot and Queen Anne's counties. The prac- 

 tice has not to this day extended to the Western 

 Shore of Maryland, where the means are unlimit- 

 ed, as is seen in a subsequent passage which will 

 be extracted from this report. 



The reader would naturally desire to know, but 

 is not informed, whether the "plastic clay" men- 

 tioned in the last paragraph but one, is recom- 

 mended for manure, supposing it to be merely a 

 clay, or as containing other useful ingredients. 



"It will have been remarked, that these deposites are 

 described as lying high above tide. It is, in fact, from 

 this boundary of the county, that the dip from north- 

 east to south-west in the marl deposite previously al- 

 luded to, becomes most apparent: occurring so far in 

 Talbot county, only a small distance below the surface 

 of the soil, it now becomes covered in the middle dis- 

 tricts by a heavy coat of gravel and sand, extending 

 from north to south from the head of Wye to the Chop- 

 tank, and reappears again at a lower level on the 

 banks, at the termination of the numerous inlets that so 

 conveniently and beautifully intersect the lower por- 

 tions of the county. 



"A reference to Map A, appended to this report, will 

 convey a better idea of the extent and numerous local- 

 ities of shell-marl in this section of the state, than a 

 bare mention of them by name could do. Suffice it to 

 say in this place, that a line drawn from the head of 

 Skipton creek, touching the intervening creek between 

 this and Dividing creek, and perhaps, prolonged to 

 the Choptank, would limit the eastern boundary of that 

 portion of the territory which embraces the great shell- 

 marl formation of the county; whilst another line 

 from the mouth of Pickering creek, enclosing the 

 western banks of Mile's river as far as the terry; 



thence, by the head of Plain dealing creek to the Chop- 

 tank, and uniting with the water boundary of the coun- 

 ty, would form its western limits. Nos. 25 to 41 on 

 the table, indicate the chemical composition of the 

 marls from the principal localities of this great de- 

 posite. 



"Nature of the materials contained in the shell-marl de- 

 posites of the Eastern Shore of Maryland. 



"It is important to become acquainted with the pre- 

 cise nature of materials contained in these deposites; 

 because upon this knowledge in a great measure de- 

 pends the judicious application to be made of them. It 

 is more especially to furnish such information that the 

 table which has been so frequently referred to was 

 made out. Some general remarks under the present 

 head seem, however, to be necessary. 



"Perhaps the true nature of these deposites is this. 

 They are vast accumulations of the exuviae of testa- 

 ceous animals, formed at a time when the portion of 

 dryland where they are now observed, was the bottom 

 of an ocean. There is no evidence that their present 

 elevated position is owing, to any upheaving of strata 

 from below — the favorite geological notion of the day 

 — nor to a simple retreat of the water from above them. 

 They are generally overlaid by a thick covering of 

 water-worn materials, such as gravel and sand, occa- 

 sionally enveloping boulders of rocks belonging to the 

 oldest geological formations; sometimes they are co- 

 vered by a heavy stratum of clay; occasionally by al- 

 ternate strata of clay, sand and gravel. In no in- 

 stance, save when they form the bottom of an in- 

 let or creek, or when they occur in the bed of a stream, 

 has their surface been observed to be denuded. Some 

 cataclysm contemporaneous with the cause of the re- 

 treat, has no doubt, occasioned the formation of these 

 superincumbent strata. It is not worth while howev- 

 er speculating about this, at present; although it may 

 be useful to know that the material by which the marl 

 is covered is not contemporaneous with the mail it- 

 self. 



"It is useful to know this, for two reasons. First, to 

 become satisfied that the nature of the superincumbent 

 soil cannot in any case be expected to partake of that 

 of the underlying stratum of marl; hence it is never 

 found to contain calcareous particles. Secondly, to 

 understand the cause of the variety in the ingredients 

 with which the marl is associated; thus we find the 

 shells sometimes enveloped in clay, at other times in 

 sand, and then again in a mixture of sand and clay, 

 these two ingredients being in very variable propor- 

 tions. 



"Now although the marl does not influence the na- 

 ture of the soil lying over it, the latter frequently 

 greatly modifies the quality of the marl beneath it. 

 The cause of this is apparent. The superincumbent 

 earth (understanding thereby the whole mass of mate- 

 rials covering the marl) consists either of clay, gravel 

 or sand, or a mixture of all these, and having, it is pre- 

 sumed, been deposited upon the marl subsequent to its 

 formation, it will, from a variety of causes, have be- 

 come mixed with it. It is, however, more especially 

 by infiltration that the marl becomes modified in con- 

 sequence of the condition of the soil above it. If the 

 latter contain fine particles of sand, as is very common- 

 ly the case, these will be taken up by the waters that 

 traverse the soil, and so charged, will penetrate more 

 or less deeply into the marl bed. Should the shells 

 there be loosely scattered in their mineral envelope, 

 which is also frequently sand, the whole of their cal- 

 careous particles may be dissolved and become re- 

 placed by a silicious deposite. The bed of fossils will 

 in this case, at least in its upper portions, exhibit an 

 accumulation of indurated casts alone of shells. Such 

 is the case in many places on Chew's island, in some 

 of the fossil deposites of Skipton creek, and in several 

 places on the Wye. It is evident that then the mate- 

 rial cannot be used as marl. When again, the super- 



