Transactions of the American Society of Civil Engineers, vol. LXX, Dec. 1910 | Page 3

gas.
5.--Tests of the various artificial breathing apparatus, and the training
of miners and of skilled mining engineers in rescue methods.
The first four of these lines of investigation have to do with preventive
measures, and are those on which ultimately the greatest dependence
must be placed. The fifth is one in which the result seems at first to be
the most apparent. It has to do, not with prevention, but with the cure of
conditions which should not arise, or, at least, should be greatly
ameliorated.
During the last 19 years, 28,514 men have been killed in the
coal-mining industries.[2] In 1907 alone, 3,125 men lost their lives in
coal mines, and, in addition, nearly 800 were killed in the metal mines
and quarries of the country. Including the injured, 8,441 men suffered
casualties in the mines in that year. In every mining camp containing
1,000 men, 4.86 were taken by violent death in that year. In the mining
of coal in Great Britain, 1.31 men were killed in every 1,000 employed
in the same year; in France, 1.1; in Belgium, 0.94, or less than 1 man in

every 1,000 employed. It is thus seen that from three to four times as
many men are being killed in the United States as in any European
coal-producing country. This safer condition in Europe has resulted
from the use of safer explosives, or the better use of the explosives
available; from the reduction in the use of open lights; from the
establishment of mine rescue stations and the training with artificial
breathing apparatus; and from the adoption of regulations for
safeguarding the lives of the workmen.
The mining engineering field force of the Geological Survey, at the
head of which is Mr. George S. Rice, an experienced mining and
consulting engineer, has already made great progress in the study of
underground mining conditions and methods. Nearly all the more
dangerous coal mines in the United States have been examined;
samples of gas, coal, and dust have been taken and analyzed at the
chemical laboratories at Pittsburg; extended tests have been made as to
the explosibility of various mixtures of gas and air; as to the
explosibility of dust from various typical coals; as to the chemical
composition and physical characteristics of this dust; the degree of
fineness necessary to the most explosive conditions; and the methods of
dampening the dust by water, by humidifying, by steam, or of
deadening its explosibility by the addition of calcium chloride, stone
dust, etc. A bulletin outlining the results thus far obtained in the study
of the coal-dust problem is now in course of publication.[3]
After reviewing the history of observations and experiments with coal
dust carried on in Europe, and later, the experiments at the French,
German, Belgian, and English explosives-testing stations, this bulletin
takes up the coal-dust question in the United States. Further chapters
concern the tests as to the explosibility of coal dust, made by the
Geological Survey, at Pittsburg; investigations, both at the Pittsburg
laboratory and in mines, as to the humidity of mine air. There is also a
chapter on the chemical investigations into the ignition of coal dust by
Dr. J. C. W. Frazer, of the Geological Survey. The application of some
of these data to actual mine conditions in Europe, in the last year, is
treated by Mr. Axel Larsen; the use of exhaust steam in a mine of the
Consolidation Coal Company, in West Virginia, is discussed by Mr.

Frank Haas, Consulting Engineer; and the use of sprays in Oklahoma
coal mines is the subject of a chapter by Mr. Carl Scholz,
Vice-President of the Rock Island Coal Mining Company.
An earlier bulletin setting forth the literature and certain mine
investigations of explosive gases and dust,[4] has already been issued.
After treating of methods of collecting and analyzing the gases found in
mines, of investigations as to the rate of liberation of gas from coal, and
of studies on coal dust, this bulletin discusses such factors as the
restraining influence of shale dust and dampness on coal-dust
explosions. It then takes up practical considerations as to the danger of
explosions, including the relative inflammability of old and fresh coal
dust. The problems involved are undergoing further investigation and
elaboration, in the light of information already gathered.
Permissible Explosives.--The most important progress in these tests and
investigations has been made in those relating to the various explosives
used in getting coal from mines. Immediately upon the enactment of
the first legislation, in the spring of 1908, arrangements were perfected
whereby the lower portion of the old Arsenal grounds belonging to the
War Department and adjacent to the Pennsylvania Railroad, on the
Alleghany River, at 40th and Butler Streets, Pittsburg, Pa., were
transferred to the Interior Department for use in these