INDUSTRIAL PROGRESS DURING THE YEAR 1871. cci 



constructing life-saving apparatus that it enables a workman 

 to enter a mine filled with fire-clamp, and to labor there for 

 hours at a time with practical immunity from danger, at- 

 tracted within the year a large share of attention in the 

 Continental and especially in the English mining districts, 

 where occasion for employing such devices is of frequent re- 

 currence. The chief merit of the "Aerophore" appears to 

 reside in the fact that its operation is continuous. We have 

 only space to state concerning it that it consists of an air- 

 pump of novel construction, a regulator, a strainer, an air- 

 tube wound on a self-regulating coil, and a lamp. 



The following table shows the production of all kinds of 

 coal in the United States since 1864 : 



Year. Tons. 



1864 22,500,000 



1865 24,400,000 



1866 28,855,918 



1867 28,861,817 



1868 31,470,114 



Year. Tons. 



1869 33,761,010 



1870 36,622,131 



1871 37,861,417 



1872 42,749,246 



1873 44,843,962 



The production of 1873 is composed of anthracite, 

 22,828,178 tons; bituminous, 22,015,784 tons; being very 

 nearly equally divided. 



In this country, the last year witnessed no extension of 

 the introduction of coal -cutting machinery. In England, 

 however, the interest in this important subject is unabated, 

 and the adoption of the machine for hand-labor is making 

 decided advances, as might be anticipated from the fact 

 that the comparative thinness of the coal-seams of that 

 country afford the best conditions for their economical em- 

 ployment. 



The so-called Gartsherrie machine appears to be the fa- 

 vorite, and we record below some considerations concerning 

 it expressed by the advocates of the system, who claim with 

 much justice for machine work: 1, a diminished cost of 

 production ; 2, an improved ventilation ; 3, a reduction of 

 waste ; and, 4, a relief to the miner from the severest portion 

 of his toil. The following tabulation, based on the result of 

 a year's working, gives the cost and the number of men re- 

 quired to remove one hundred and twenty yards of coal 

 (equal to one hundred and thirty tons) holed by the Gart- 

 sherrie coal-cutter : 



