Page:The Journal of geology (IA journalofgeology21894univers).pdf/228

operation until 1861, during which time its labors seemed to have been centered upon systematic county work, leading to the production of special county maps and reports. A table contained in the fifth report of progress shows that, up to the end of 1860, field work had been completed in eighty counties, and of these, reports had been made upon thirty-three; in a considerable number of other counties more or less work had been done. Five of these reports were contained in the Second Annual, and twenty more constitute a report issued in 1873; others were probably used in the preparation of the county descriptions of the other reports of 1873 to 1874. In addition to this work, during the period of the first survey, Professor Swallow made an official report of ninety-three pages on the Southwest Branch of the Pacific Railway.

Reviewing, briefly, this work of the First geological survey, we must recognize as remarkable and excellent the classification of the rocks which are evolved, as well as the general accuracy with which the distribution of the formations was defined, especially when the short time is considered; avowedly under the control of Hall's New York classification and nomenclature, published in 1843, though undoubtedly assisted, yet not misled by Owen's results, Swallow and his assistants established a table of formations, and outlined a geographical map of the state which remains to this day unchanged in its larger features.

From 1860 to 1870, geological work was nearly at a stand-still in the state. During this period, however, Professor Swallow, as professor of geology in different capacities, extended their observations in the state, and published the results in scientific journals or in the proceedings of scientific societies.^[1]

In March, 1870, an act was passed authorizing the Second geological survey. The provisions of this act were in the main similar to those of the first, with the exception that the Bureau was placed under the control of a board of managers of nine