594 C. WHITTLESEY ON THE PHYSICAL 



Triangula tions for Dip of the Lower Coal Seam. 



From the National Road northward, along the westerly and northwesterly border of the 

 Ohio coal field, I have data for a connected series of planes, to the Pennsylvania line, at 

 Brookfield, in the county of Trumbull. As the courses and distances between points are 

 not obtained from maps of a large scale, they cannot be strictly accurate ; neither are the 

 levels, in all cases. But there are sources of error arising from the irregularity of the 

 strata, which are fully as large as those of the surveys and elevations. The results are 

 therefore put forward subject to future corrections, but with much confidence that they are 

 close approximations. 



Triangle No. 1. — Brownsville, Licking County, Newcastle, Coshocton County, and " Treaty 

 Line," on the Killbuck, Holmes County. According to Mr. Foster's Report, the lower coal at 

 Brownsville, on the National Road, is two hundred and seventy feet above Lake Erie. From 

 thence to Newcastle, on the west line of Coshocton County, is north 9° east, 25.8 miles, and 

 the elevation of the lower coal is there five hundred and thirteen feet above Lake Erie. From 

 Newcastle to Cameron's Bank, at Treaty Line, four miles north of Millersburg, is north 32^° 

 east, 22.2 miles. The base of this triangle, from Brownsville to Treaty Line, is 47^ miles, 

 course north 20° east ; the apex being at Newcastle. If we regard the upper Newcastle seam 

 as the lowest of the coal series, the dip is seventy-one feet per mile, which is greater than 

 I have anywhere discovered it in so large a plane. By using what Messrs. Winchell and 

 Newberry regard as a fake coal seam, near Newcastle, which is five hundred and thirteen feet 

 above Lake Erie, as the true lower seam, corresponding to Brownsville and Massillon, it 

 comes into harmony with other results. I therefore regard it as seam No. 1 of the series ; 

 the dip of which is south 69° east, 27^ feet per mile. 



Triangle No. 2. — Darling's Bank, near Warsaw, Coshocton County, 348 feet A, Treaty 

 Line, Cameron's Bank, and mouth of Newman's Creek, near Massillon. From Darling's, 348 

 A, to Treaty Line, 365 feet A, is north 15° east, 18 miles ; Treaty Line to Massillon, 346 feet 

 A, north 54£° east, is 23.3 miles. Base line, north 35° east, 39 J miles. The lower coal seam 

 at these three points is so nearly level that the greatest dip is only two (2) feet per mile, 

 direction south 55° east ; the line of bearing coinciding with the base, from Darling's to 

 Massillon. 



Triangle No. 3. — Massillon, Coal Hill, Tallmadge, and Briar Hill. The central part of 

 Coal Hill, Tallmadge, 505 feet A, is distant north 21° east from the mines at the mouth of 

 Newman's Creek, 22.8 miles, and Briar Hill 318 feet A, north 65° east, 53 miles. In this 

 plane the line of greatest inclination bears south 29£° east, at the rate of 9.9 feet per mile. 

 Both the Massillon and the Briar Hill coal seams produce the best of iron when used in a 

 raw state, and are therefore the most valuable beds in Ohio. If there was a reasonable cer- 

 tainty that this seam extended through, of the same quality, from the valley of the Tusca- 

 rawas to that of the Mahoning, it would furnish an inexhaustible supply. There are no 

 valleys between those streams deep enough to cut the plane of coal seam No. 1 ; and the 

 researches thus far made have failed to discover it. 



Outline Geological Map. 



Although from a bird's-eye view, Ohio appears as a vast plain, without mountain ranges, 

 the outcrop of the strata present in their details very irregular lines ; the hills and ridges 



