The Origin of Coal (open access)

The Origin of Coal

From Introduction: "The purpose of the studies that form the basis of this report was to learn from microscopic examinations of coal how far and in what ways the grouping of coal by types depends on differences in the kinds of plant material from which it was formed and on the conditions of its accumulation, or how far the special characters or qualities of coal of any type were determined by the nature and the state of the plate debris from which the coal was formed."
Date: 1913
Creator: White, David & Thiessen, Reinhardt
System: The UNT Digital Library
Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910 Part 2. Descriptions of Samples (open access)

Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910 Part 2. Descriptions of Samples

From Introduction: "This volume contains the descriptions of the samples whose analyses are published in the preceding volume, Part I of this bulletin. The descriptions have been compiled from the notebooks of the persons who collected the samples, have been condensed from accounts given in published reports of the United States Geological Survey, or have furnished by the collection themselves. Inasmuch as the descriptions represent the work of many persons during a period of six years, and inasmuch as they were recorded under widely differing conditions, they necessarily vary in fullness detail."
Date: 1913
Creator: Lord, N. W.
System: The UNT Digital Library