402 JOSEPH STRUTHERS 



finery, where the sterile sand is segregated by mechanical 

 concentration with hot water. The asphaltic material rises 

 to the surface and passes to the reducers, where it is brought 

 to the proper consistency by the appHcation of heat and sub- 

 sequently strained and barreled for shipment. The products 

 vary with the demands of the market, and range from a semi- 

 liquid on the one hand to a hard and brittle form on the other. 

 Very little of the latter is made, however, on account of the 

 large amount of time and fuel required to produce it. 



The principal bituminous sandstone deposits in Ken- 

 tucky are in Logan, Warren, Edmonson, Butler, Grayson, and 

 Breckinridge counties, occupying an area of 20 by 50 miles in 

 the central part of the state. The deposits are in fine grained 

 sandstone of the subcarboniferous formation, and from geo- 

 logical evidence the asphaltum represents the residual matter 

 from preexisting beds of petroleum. The numerous deposits 

 in Grayson and Edmonson counties vary both in richness and 

 magnitude, the range in the thickness of the beds being from 

 2 to 20 feet. But few of these deposits, however, are of com- 

 mercial value. The richer deposits lie between strata of black 

 rock from 1 to 2 feet thick, and the intervening asphaltum 

 ledge varies in thickness from 3 to 15 feet and contains from 

 5 to 15 per cent of bituminous matter; below 4 per cent as- 

 phaltum content the material merges into black rock. 



Up to the present time only those deposits lying conveni- 

 ently near railroad or river have been developed, and of such 

 only those have been developed, and of such only those have 

 been worked, which offer the least difficulty in the way of 

 imcovering. No tunneling or drifting has yet been attempted. 

 At Bowling Green there is a 200 ton refining plant, equipped 

 with corrugated rolls. The moisture in the material as it 

 comes from the crushers is expelled by means of steam jets. 



A property 4 miles northeast of Russellville, Logan coun- 

 ty, has been developed quite extensively, the quarry face show- 

 ing a 17 foot asphaltum ledge. The plant of this company in- 

 cludes a 250 ton gyratory crusher and plain 14 by 18 inch rolls. 

 Quarries, mill, and tipple are connected by H niiles of narrow 

 gauge track, and at the end of the year the rolling stock equip- 

 ment consisted of 45 cars. At Louisville, the operating com- 



