United States Bureau of Mines Bulletin 636

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.

United States Bureau of Mines Reports

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

Chapitre 16. Les habitudes de lecture

L’alphabétisation et l’illettrisme michel verrette Si la notion d’alphabétisation est difficile à cerner au cours des siècles précédents, au XXe siècle la notion elle-même devient volatile. Il est impossible de porter sur elle un seul regard et d’avoir à son sujet une opinion définitive. Au tournant du XXe siècle, même si le critère de la signature peut être encore considéré comme valable pour évaluer le taux d’alphabétisation, ce sont désormais les notions de lecture et d’écriture élémentair..

United States Bureau of Mines Bulletin 591

From Summary and Introduction: "Descriptions are presented for the synthesis of authentic specimens of tar acids and tar bases. An appendix contains the ultraviolet and infrared spectra of 189 individual tar acids and tar bases.