2. Three to four miles 

 west of Pov. Gap, 



•i. Two miles next 

 New Eiver Gap, 



4. Five miles west of 

 New River Gap, 



Lesley.] 3g [May. 



waste and high per cent, of ash, and the competition of Pennsyl- 

 vania portable anthracite. 



The quantity available by gangways driven in from New River, 

 Poverty Gap, and the other breaks in Brush Mountain, where the 

 real supply is to be obtained for any future trade, is an important 

 question, and the answer may be tabulated as follows : 



A, being the amount above water-level of all gangways. 



B, being the amount above water-level of Poverty Gap. 



C, being the amount below water-level to the fault. 



A. B. C. TOTAL. 



1. Ten miles east of ) 



„ , ,^ J- 850,000 1,560,000 11,500,000 12,910,000 tons. 



Poverty (xap, } ' 



i 250,000 3,500,000 3,750,000 tons. 



i Much less coal. 2,000,000 2,000,000 -f tons. 



I 750,000 + 



It is supposed that at 3 cents per ton per mile, a branch road ex- 

 clusively for coal will pay 6 per cent on a capital, if its tonnage is at 

 least double the number of dollars which the road has cost per mile. 

 A road costing $15,000 should send over at least 30,000 tons per 

 annum. 



The data from which the above calculation is made, are as follows : 

 The distance from Poverty Gap (the terminus of a branch road from 

 Christiansburg) to Shlusher's, along the coal beds, is ten miles, 17,000 

 yards; the line of highest outcrops strait, the line of water-level 

 gangway-mouths in the different ravines rises regularly eastward ; 

 the greatest breastings from the gangway, above water-level, at Po- 

 verty Gap, is 350 feet; the least breasting at Shlusher's is nothing; 

 the height of Shlusher's coal crop above Poverty gangway, 250 feet; 

 the loss by ravines at every half mile, say one-quarter ; the average 

 yield of B say 3 feet, of A 2 feet; loss in mining one-third. 



Mr. Gerhard presented specimens of mammoth powder in 

 use in Gunnery. 



Pending nominations Nos. 456, 457, 458, and new nomina- 

 tions Nos. 459 to 465 were read. 



The communication of Mr. Prettyman was referred to a 

 committee consisting of Prof. John C. Cresson, Mr. Peale, 

 and Mr. Baldwin. 



And the Society Avas adjourned. 



