Report on the projected Survey of the State of Maryland. 33 



3d. Extensive deposits of day, on the slope of Winding ridge, 

 east shore of Yohogany. This deposite contains nodules of argilla- 

 ceous iron ore. It rests upon the sandstone, and is covered by 

 a continuous stratum of calcareous marl. — The ore, promiscuously 

 extracted from the bed, has been found to smelt itself." 



Associated with the deposites, there has been observed in the stratum 

 of ferruginous clay, overlying the coal, (as remarked in note 1st ; 

 above,) nodules of a mineral substance, consisting of lime, clay and 

 oxide of iron, answering very nearly the description of what by 

 English writers is termed Parker^s cement, but better known in this 

 country under the name of Roman cement. This article will proba- 

 bly hereafter prove susceptible of most useful application. 



Manganese, some of which is of very good quality, has been found 

 on Bear creek. It occurs also on Keyser's ridge, five miles south of 

 the national road. 



The Yohogany furnace, on Bear creek, is situated in the midst of 

 these resources. With an immense amount of water power at com- 

 mand, and under an active and intelligent management, it requires 

 nothing but greater facilities for sending its valuable products to mark- 

 et. 



Finally, another object which has excited some degree of interest 

 in this portion of Allegany county, is the existence of a cave towards 

 the head waters of the Yohogany, reported to be of great extent and 

 to have furnished a considerable quantity of crude saltpetre. A sim- 

 ilar cave was observed near Hancock, Washington county, which is 

 also said to have yielded this salt. There is a similar one at the 

 foot of the South mountain. An exploration of these caves might 

 bring to light something of interest ; although it is presumed to be a 

 subject of but secondary importance. 



In the commencement of this report, the undersigned have allud- 

 ed to the circumstance of embracing in their examination an inquiry 

 into the hydrology of the state. They have not lost sight of the 

 importance of this object ; but have to regret that the short time al- 

 lowed them for investigating so many subjects of interest has not 

 permitted them, so far, to collect a sufficient number of facts to ar- 

 rive at any but a very partial result. 



The undersigned will now close the remarks, which for the pres- 

 ent they have to make on the geology of Maryland. They hope it 

 will be perceived that their main object in ascertaining upon scien- 

 tific principles the true mineral constitution of the State, has been to 



Vol. XXVII.— No. 1. 5 



