Report from the U.S. Bureau of mines discussing the use of infared and ultraviolet-visible spectrometry to study the structure of coal and coal extracts.

From Introduction: "In connection with the overall research by the Bureau of Mines on the nature of coal and its products, and extensive investigation was conducted on the composition of the resins from pitch of low-temperature tar. The pitch resin is that material in pitch or tar that is insoluble in saturated hydrocarbon solvents. It varies in appearance from a dark brown semisolid to a black, granular solid."

From Abstract: "This bulletin is a detailed study of low-temperature, entrained-bed carbonization of a Texas lignite. The lignite was from the Sandow strip mine and is representative of the Rockdale formation of the Wilcox formational group.

Report discussing an extensive characterization on the neutral oil components in a low-temperature bituminous coal tar. A total of 133 individual compounds was identified with respect to individual isomers and at least 55 other compounds were indicated to be present. Comparisons and descriptions of the compounds are presented.

From Abstract: "Optical Properties of U.S. coals of differing rank have been investigated by the Bureau of Mines for about 20 years. These investigations have been made to further the development of an objective basis for petrographic analysis of coal and to add knowledge of the structure and composition of coal and coal components by determining their optical constants in various regions of electromagnetic spectrum."

Report issued by the Bureau of Mines on the anthracite coal in the Bottom Red Ash Bed in Pennsylvania. The coal samples were analyzed for thickness and geologic structure. The amount of recoverable coal was also estimated. This report includes tables, maps, and illustrations.

Report issued by the Bureau of Mines discussing the Ringelmann smoke chart. This report serves as a revision to a previous report covering the Ringelmann chart. As stated in the abstract, "since instructions on its use are not shown on the recent edition of the chart, those included in this revision of the previous Bureau of Mines publication now are necessary complement to the chart. More detail regarding the use of the chart is included than was given in the earlier version" (p. 1). This report includes tables, and illustrations.

From Abstract: "In addition to elementary statistical theory the material presented in the bulletin includes: (1) Certain special statistical techniques that have been found useful in mining applications; (2) problems, implications, and limitations that may be encountered in applying these techniques in mine sampling and evaluation; and (3) numerous examples to demonstrate application of the theory and techniques." From Introduction: "This report presents some of the statistical techniques that are useful for evaluating a mineral deposit and makes it possible for the analyst to derive much additional information from a set of assay data."

From Introduction: "This publication includes the laws of the States, the District of Columbia, Puerto Rico, and the Virgin Island through 1964. Only those portions of the workmen's compensation laws which apply to or are related to and deletions from the basic law have been incorporated into the text of the law, thus making it unnecessary to search out the various amendments made each year."

Report issued by the Bureau of Mines over a study on "stress determinations in an area known to be under high stress concentration induced by prior mining operations" (p. 2). The geology, procedures, and instrumentation are discussed. This report includes tables, illustrations, and photographs.

From introduction: "This report contains the results of measurements to obtain the heats of formation of forsterite and chrysotile; entropies at 298.15 K of two polymorphs of serpentine, chrysotile and antigorite; and high temberature heat content increments for antigorite. These results have been combined with other pertinent data to derive heat and free energy values at high temperatures."

Report issued by the Bureau of Mines discussing the thickness of coal seams mined in the United States between 1945 and 1965. Locations, and production of coal seams are presented. This report includes tables.

From Abstract: "This bulletin presents, in collected and tabulated form, Bureau of Mines and American Gas Association (BM-AGA) carbonization data pertaining to the chemical analysis of tars and the characterization of tars and light oils obtained from U.S. coals."