PREFATORY NOTE. 



The popular demand for a complete series of the Annual Eeports of 

 tlie United States Geological Survey of the Territories under my 

 charge has been so great that the Secretary of the Interior has ordered 

 the printing of a second edition of the first, second, and third annual 

 reports in one volume. The survey in its present form commenced 

 in the spring of 1867, with a small appropriation of $5,000 made by 

 Congress for the examination of Nebraska ; in 1868 it was continued in 

 the Territory of Wyoming with a similar sum of $5,000 ; in 18G9 it was 

 extended to Colorado and JTew Mexico, with an increased appropriation 

 of $10,000. During the years 1867 and 1868 the survey was conducted 

 under the General Land-Office, and the first and second annual reports 

 were included in the reports of the Commissioner. Early in 1869 the 

 survey was placed by Congress under the Secretary of the Interior, and 

 the third annual' report was published as an independent volume. 

 These reports are now entirely out of print. 



Although they were written in the field and forwarded to Washington 

 in detached portions, and, in the case of the first and second reports, 

 printed without the supervision of the writer, I have thought it best to 

 make no alterations or additions in the present reprint, but to let the 

 rejDorts continue to mark the steps of progress of the survey from year 

 to year. 



In the spring of 1870 I presented before the Committee on Appro- 

 priations of the House of Representatives a plan for the geological and 

 geographical exploration of the Territories of the United States. This 

 j)lan looked forward to the gradual preparation of a series of geo- 

 graphical and geological maps on a uniform scale, embracing each of 

 the Territories in accordance with the boundary-lines. In this way 

 these max)s would become of great practical as well as scientific value 

 to each of the Territories examined. In accordance with this plan, 

 maps of Kansas, Nebraska, Dakota, Montana, Idaho, Utah, Wyoming, 

 Colorado, and New Mexico are in an advanced state of preparation. As 

 soon as the details of the geology are more fully worked out, these 

 maps will be issued. 



F. V. HAYDEN, 



United States Geologist. 



Washington, ilia?/, 1873. 



