MINE TIMBER VS. CONCRETE AND STEEL 



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F. S. Circular 111, issued Oct. 10, 1907 called Prolonging the Life of Mine 

 Timbers, by John M. Nelson, Jr. It is from Mr. Nelson^s circular that the 

 diagram (Fig. 1) and the photograph (Fig. 2) have been taken. 



Experiments with concrete and steel construction have been carried on 

 for a number of years. The mine which is best fitted out with these modern 

 appliances is the Allport Mine at Barnesboro, Pennsylvania. It is to be 

 noted that in connection with the new government Bureau of Mines a gov- 

 ernment mine is to be opened at Brucetown, Pennsylvania, in the near future. 

 It is the object of Dr. Holmes, Director of the Bureau of Mines, to make this 

 mine, run by the government, typical of actual mining conditions. Accord- 

 ingly, parts of the mine are to be timbered in the old way (see Fig. 3), and 

 parts are to have all modern appliances. It is proposed in connection with the 

 government mine, to change the testing chamber where explosives are tried 

 out and where experiments in the explosibility of coal dust are made, from 

 Pittsburg to the new government mine at Brucetown. By having this chamber 

 in connection with the mine it is thought that experiments can be made first in 

 the chamber and then in the mine itself. In this connection, it is noteworthy 

 that the part of the mine in which explosions are to be set off is to be 

 entirely constructed of concrete and steel. (See Fig. 4.) And the government 

 expects to be able to entirely control explosions within this area. 



A new era for the mine is approaching, an era without the old waste, the 

 old lack of efficiency. Explosion and fire with its attendant loss to life and 

 property will in the future be done away with. The cost of "timber" per ton 

 of coal will be made smaller and the annual timber consumption will be 

 materially decreased. 



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FIG. 4. 



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