_Character of the Work._--The United States Geological Survey has been
engaged continuously since 1904 in conducting investigations relating to
structural materials, such as stone, clay, cement, etc., and in making
tests and analyses of the coals, lignites, and other mineral fuel
substances, belonging to, and for the use of, the Government.

Incidentally, the Survey has been considering means to increase
efficiency in the use of these resources as fuels and structural
materials, in the hope that the investigations will lead to their best
utilization.

These inquiries attracted attention to the waste of human life incident
to the mining of fuel and its preparation for the market, with the
result that, in May, 1908, provision was made by Congress for
investigations into the causes of mine explosions with a view to their
prevention.

Statistics collected by the Geological Survey show that the average
death rate in the coal mines of the United States from accidents of all
kinds, including gas and dust explosions, falls of roof, powder
explosions, etc., is three times that of France, Belgium, or Germany. On
the other hand, in no country in the world are natural conditions so
favorable for the safe extraction of coal as in the United States. In
Belgium, foremost in the study of mining conditions, a constant
reduction in the death rate has been secured, and from a rate once
nearly as great as that of the United States, namely, 3.28 per thousand,
in the period 1851-60, it had been reduced to about 2 per thousand in
the period 1881-90; and in the last decade this has been further reduced
to nearly 1 per thousand. It seems certain, from the investigations