Report issued by the U.S. Bureau of Mines detailing the laboratory-scale tests of the efficiency of the Trent process in cleaning coal, in which powdered coal, water, and oil is agitated or beaten together to remove impurities. The report includes details in tables detailing the efficiency varying the type and amounts of coal, oil, and water on the process.

This document reports the economic geology of the Lacasa area, Ranger district in North-Central Texas, with fieldwork done in April and May of 1919.

Booklet describing the biology of Alabama in two sections: (1) physiography and life zones, and (2) mammals. It also includes an annotated species list of mammals, bibliography, and index starting on page 81.

Report describing the functions and operations of the United States Bureau of Commerce and its divisions during the fiscal year.

Technical paper issued by the Bureau of Mines over studies conducted on fire resistance on building columns. As stated in the introduction, "the purpose of this investigation is to ascertain (1) the ultimate resistance against fire, of protected and unprotected columns as used in the interior of buildings; (2) their resistance against impact and sudden cooling from hose streams when in a highly heated condition" (p. 12). This paper includes tables, illustrations.

Technical paper issued by the Bureau of Mines over quarry accidents reported during the year of 1919. The results of the accident reports collected are presented and discussed. This paper includes tables.

Technical paper issued by the Bureau of Mines over the development of gas masks designed for fighting fires. The characteristics of the different types of masks in development are presented. This paper includes tables, illustrations, and photographs.

Report issued by the Bureau of Mines covering petroleum laws of the U.S. and surrounding oil producing countries. As stated in the preface, "this bulletin includes the petroleum laws of (1) United States; (2) the several oil-producing States; (3) Canada; (4) Mexico; (5) the Republics of Central and South America" (p. iv).

Report issued by the U.S. Bureau of Mines on the characteristics and behavior of oil and coal distillation processes. The effectiveness of the distillation processes and the properties of the oil and coal mixtures are presented. This report includes tables, graphs, and illustrations.

Report discussing the the development of milling practice in Boulder County, the ore-dressing methods in use, and the local manufacture of ferrotungsten and tungstic oxide. Figures giving the production of tungsten concentrates in the Boulder district, in the United States, and in the world; data on the buying of tungsten ores; costs of production; and the normal tungsten requirements in this country are presented.

Note presenting an experiment to obtain information regarding the relationship between the coefficients for flow in the two directions through an inlet. The results indicate that the ratio of the orifice discharge coefficient from standard orifice to the discharge coefficient from reverse flow is always less than unity, but approaches unity with increasing ratio of box area to orifice area, and that even for a ratio of areas as low as twenty the ratios of the coefficients is not much less than unity.

From Origin of Federal Explosives Act, October 6, 1917: " A competent force from the Bureau of Mines was then assigned to study the laws and ordinances of countries, States, and municipalities in which lawas and ordinances regulating explosives have been enacted, and especially to ascertain how these laws had been modified by the necessities of the existing state of war, and, also, wherein the proposed law might conflict with or overlap the jurisdiction of existing laws. This incomplete enumeration of the peace-time uses of explosives shows that the quantity consumed is large. A more definite conception is given by the following statistics of production, to which is added statistics for exportation that disclose something of the effect of war on the explosives industry."

From Introduction: "This paper covers part of the investigations carried on by the United States Bureau of Mines in cooperation with the Idaho Bureau of Mines, the University of Idaho, and certain mining companies of the Coeur d' Alene region. Although the results of the tests included in this report are not to be considered final, they indicate possibilities and may suggest others leading to a solution of the problem of separating lead and zinc sulphides by differential flotation in the treatment of certain ores."