Report on the projected Survey of the State of Maryland. 31 



the slate roof is sandstone in thick layers and often of a quality suita- 

 ble for the various purposes of freestone in building. A preference 

 is given to those mines that lie deep, which are in a moist sit- 

 uation, and have a considerable height of hill over them : the coal 

 from such mines, being more pure and solid, is quarried in much 

 larger blocks, and is much less liable to crumble and waste in hand- 

 ling, than that from mines situated so near the top of the hills as to 

 be too dry and to have but little depth of earth over them." — pp. 93, 

 94. 



The analysis of a specimen of the coal from the large bed, known 

 as Frost's mine, about half a mile southwest from Frostburg, gave 

 the following resuhs : — 



Carbon, ....... 70. 



Bitumen, 20.5 



Earthy matter, - G. 



Water, 3.5 



100. 



It is thus shewn to be of that variety distinguished mineralogically 

 as slaty coal', which is ranked among the best, as it burns easily, with 

 a bright and durable flame, swells and agglutinates, or cakes as it is 

 termed, and leaves little residue. 



From this view of the extent and condition of the coal deposites 

 in this district h will be seen, that should the projected schemes of 

 communication between the Chesapeake bay and the western waters, 

 by means of canals and rail roads, be effected no further even than 

 Cumberland — and there is but little doubt that the communication 

 will soon extend thus far, there will be furnished a convenient out- 

 let for an amount of coal which can be estimated only by hundreds 

 of millions of bushels. 



But this is not the sole district in which the coal deposites occur. 

 Another, probably of equal extent, lies beyond the Great Back-bone 

 ridge, along the valley Yohogany, and extending as far as the most 

 southern limits of Maryland ; which by way of distinction, may 

 be called the Yohogany coal district. It has been remarked of this 

 western coal region, that the beds within it are generally thicker 

 than those of the Frostburg district. That bed, for example, which 

 seems to correspond with the fifteen feet vein in Brant's mine, is 

 found near the heads of the Potomac to exceed twenty feet in thick- 

 ness. Time, no doubt may be expected to elapse, before these 



