16 Report on the projected Survey of the State of Maryland. 



If, first, we inquire into the nature of the soil by which these rocks 

 are covered, it seems proper to base this inquiry upon the considera- 

 tion that the soil (so far as its mineral constitution is concerned) is 

 produced by the disintegration of the rock which immediately under- 

 lies it : whenever observed to be otherwise, it is presumed that it will 

 always be found to have arisen, either from the circumstance of an 

 encroachment of the tertiary formation upon the primary, or from 

 partial transportations of soil from one spot to another by causes al- 

 ways appreciable. This view it is deemed important to take, as the 

 only one calculated to lead to any general and positive results of val- 

 ue to agriculture. Thus every farmer in Baltimore county is aware 

 of the higher estimate which is put upon the red soil of some districts, 

 than upon the lighter colored soils of an adjoining one. Now, the 

 red soil, as it is termed, is known to be produced by the decomposi- 

 tion of that variety of rocks, called hornblende rock; while the ad- 

 joining soil is derived from some other of the granitic aggregates. 

 On the other hand, those portions of the same county that are de- 

 signated as barren, are equally well known to occur principally 

 among the magnesian and talcose rocks. Generally speaking, then, 

 the mineral constituents of these soils will be found to correspond 

 with those of the rocky strata beneath them. Although it is a re- 

 markable fact in relation to the limestone soil, that its constituents do 

 not indicate it to have been produced solely by the disintegration of 

 the subjacent rock. Still however, the limestone soil, like the other 

 soils that have been mentioned, is peculiar, and it is uniform, as re- 

 gards superposition upon limestone rock ; and as it shews no evi- 

 dence of having been transported, must be classed among the prima- 

 live or original soils, whatever may have been the circumstances, 

 hereafter to be discovered, that have occasioned its production. 



If this view of the original constitution of the soils lying over the 

 primary rocks be a correct one, and it is confidently believed to be 

 soj it follows, that the first step to be taken by which to serve the ag- 

 ricultural interest of this portion of our state, is to discover and to es- 

 tablish the nature of each geological formation within it. 



It is also a matter of interest to the farmer to know the limits of 

 these formations. It interests him for example, to be made acquaint- 

 ed with the nearest spot from which he can derive his material for 

 obtaining lime. Yet, even as regards the limestone formation, its lim- 

 its have not been satisfactorily determined. From this circumstance, 

 much inconvenience and disappointment have already arisen. Thus, 



