79 



average contents per piece already determined. It will be noted that 

 91.24 per cent of all wood used in mines is in the form of round or hewn 

 products of which but 7.13 per cent are legs and bars of sizes capable 

 of yielding lumber. Thus 84.12 per cent of all the wood used in coal 

 mines consists of relatively small props, mine ties, and lagging, which 

 utilizes trees down to from 3 to 4 inches in diameter breast high. 



The only use of wood comparable to this in closeness of utilization 

 is as cordwood for fuel. But the economic value of mine timbers is 

 much higher than that for cordwood, since for the consumption of .246 

 cubic feet, or, at 80 cubic feet per cord, of 00.3 per cent of a cord, one 

 ton of coal is obtained, having a fuel value, at .8 tons per cord, of 406.5 

 times that of the wood consumed. It requires a total of 246,37.5 cords 

 of wood to mine all the coal produced in Illinois, while if wood were 

 substituted for coal as fuel, the requirements would be 100,1.52,438 cords 

 as against an actual output of 1,024,614 cords, or not much over 1 per 

 cent of these requirements. It is therefore evident that if wood must 

 be grown to supply fuel, its most economical use is by converting this 

 wood into coal through the mining industry, and that the land required 

 to produce mine props is performing a service of very high value to the 

 community. 



Cost of Mining-timbers 



These relative values are reflected in the prices paid for mining 

 timbers as compared with those for cordwood. The average price paid 

 at the mines for all classes of timber reduced to cubic feet was in 1921, 

 18.3 cents per cubic foot, which at .246 cubic feet per ton of coal mined 

 gives a cost of 4. -5 cents per ton of coal for wood delivered at the mine.* 



The price for the larger sizes in the form of legs and bars, was 26.7 

 cents, or 46 per cent greater than this average, while for mine props it 

 was 16.2 cents per cubic foot, or 11.5 per cent lower. The larger dimen- 

 sions thus command a price per cubic foot 64.3 per cent greater than the 

 smaller props. 



• Costs of Timber Delivered at Mine. 1921 

 Summary of Results from Comlming Figures of Harry E. Tufft and R. B. Miller 



TufTt 8,845.650 tons $302.2!I8 3.5 cents per ton 



Miner 14,049.475 tons 717.601 5.1 cents per ton 



Combined 22,895.125 $1,013,899 4.5 



The discrepancy in tonnage between this showing for Miller and the number of 

 tons reported on by him in the foot-note on page 78 is expiaim d by the fact that for 

 2,592,685 tons he had cubic feet of wood requirement but no data on costs. 



