COAL MINING. 225 
ing the whole coal field throughout, the conditions for cheap and sys- 
tematic mining are unusually favorable. The floor of mines is compara- 
tively level, the usual dip, except in local cases, being 25 or 30 feet to 
the mile. 
Over large areas of the coal field, where the country is hilly, the 
beds of coal in course of development come to day or crop out in 
the hillsides, and admit of what is termed drift or level-free mining. 
Under such conditions the seam is followed into the hill, and the waters 
of the mine discharge themselves by gravitation. Care is taken in 
opening a drift mine to select the lowest place on the property, if the 
circumstances will admit of it. 
In regions where level-free mining is impracticable, two methods of 
sinking for coal are followed: one is by opening perpendicular shafts, 
and the other by sinking slopes ata pitch of from 25 to 35 degrees. 
Slopes are, however, rarely opened where the coal is found more than 
150 feet below the surface, for below this depth it is more costly to sink 
and deliver coal by a slope than by a perpendicular shaft. Under favor- 
able conditions slopes ‘are largely a matter of taste on the part of 
managers ; they are never cheaper than shafts. 
- The coal business has localized itself and the various districts in 
which the mines are opened are known by appropriate names. There 
are now a dozen districts in the State in which the coals possess peculari- 
ties by which they are known, as the Mahoning Valley region, the 
Jackson County region, the Ironton region, the Pomeroy region, 
the Bellaire region, the Steubenville region, the Salineville region, the 
Cambridge region, the Dell Roy region, and the Coshocton region. 
Sometimes two or more qualities of coal are drawn from the same bed, 
as, for example, the Brier Hill coal and the Mineral Ridge coal, both 
of which are mined in the Mahoning Valley, or the Nelsonville, Straits- 
ville, Shawnee, Sunday Creek and Monday Creek coals, all of which 
are drawn from the great seam of the Hocking Valley region. 
All other conditions being equal, the best seams are selected and 
opened. There are thousands of acres of as good coal still untouched in 
the coal field as any in present course of development, but for want of 
railroad facilities, or because of its lying in the interior of the coal field, 
it remains for the time being unwrought. The severe competition of 
the trade obliges the mining operators to take advantage of all the 
conditions in developing the mines. The districts which are furthest 
