Report on the projected Survey of the State of Maryland. 27 



On the western slope of the South mountain, the epidote rocks and 

 amygdaloids, are again met with ; but in descending into Pleasant 

 valley, which lies between the mountain and a more limited range of 

 hills, known as the Elk ridge, there is observed a formation of lime- 

 stone, from which statuary marble of superior quality, has been ob- 

 tained. The principal quarries of this marble, are in the vicinity of 

 Boonsborough. At the debouche of this valley, there is an extensive 

 deposite of iron ore, which in its chemical composition is analogous 

 to that described as occurring on the eastern slope of the Catoctin, 

 but it is free from phosphate of iron. It is technologically termed 

 pipe ore, and sometimes limestone ore, from the circumstance of its 

 usually occurring in that rock. The metal obtained from it is of ex- 

 cellent quality, and well adapted to the making of bar iron. The 

 Antietam Furnace is in part supplied with this ore from a place two 

 miles above Harper's Ferry on the Potomac and Maryland side of 

 the river, and from a similar deposite on the Virginia shore, about 

 six miles above the ferry. The same ore again occurs in the nor- 

 thern portions of the West slope of the South mountain. 



The other notable localities of iron ore within the limits of this divi- 

 sion, are on the eastern slope of Sideling hill, beyond the Conoloway. 

 It is there associated with manganese. 



Williamsport, situated near the confluence of the Conocoheague 

 and the Potomac, has been frequently indicated as the centre of a 

 district, in which anthracite coal might confidently be expected to 

 occur. The undersigned are not aware of the grounds upon which 

 this assertion has been made. As was stated in regard to certain 

 parts of Frederick county, there is nothing which absolutely forbids 

 it, but neither is there any thing which in their knowledge indicates 

 it. The known region of anthracite, supposing it necessarily to ex- 

 tend from Pennsylvania through Maryland, would not be found to 

 correspond with this portion of our state ; it would rather strike far- 

 ther west, between Hancock and Sideling hill. The undersigned 

 have not been wanting in endeavors to impress this view upon the 

 minds of those of their fellow citizens, who seemed to take especial 

 interest in the subject ; and a confirmation of their opinion, they think, 

 may be found in the recently reported discoveries of coal on Sleepy 

 creek, in Virginia. 



It has been said that the line of the Pennsylvania anthracite depos- 

 ites would, if continued, strike in this division near Hancock. No 

 such continuation has been observed ; but yet the geological interest 



