January 1, 1897.] 



SCIENCE. 



9 



American troops, he accepted the position 

 of surgeon in the United States army, and 

 finally returned with Col. Doniphan's com- 

 mand. His narrative, with scientific ap- 

 pendices, was printed by order of Congress. 

 In it he notes Cretaceous rocks on the Great 

 Plains, Cretaceous limestones with Inocer- 

 avncs near Las Vegas, and the sandstones 

 near Santa Fe ' thrown back at an angle of 

 100 degrees by the uplift of the granite.' 

 Silurian limestones were seen near El Paso, 

 and both Silurian and Cretaceous lime- 

 stones around Chihuahua, Mexico. He does 

 not appear, however, to have met with any 

 outcrop of coal-bearing rocks. He remarks 

 on a decadence of mining in Mexico and 

 gives interesting statistics on the ancient 

 silver and copper mines in the State of Chi- 

 huahua. In his report he gives what is 

 called a geological map of the regions tra- 

 versed, in which the occurrence of rocks of 

 the different descriptions are indicated by 

 words. 



1847. In 1847 under the auspices of the 

 United States Land office, of which James 

 Whitcomb had now become Commissioner, 

 David Dale Owen commenced his final sur- 

 vey of the Northwest Territory comprising 

 parts of Wisconsin, Iowa, Minnesota and 

 Nebraska. Although this work only inci- 

 dentally extended into the region west of the 

 Mississippi valley, it forms an important 

 epoch in the geological history of the West, 

 for it was the first systematically organized 

 geological survey conducted under govern- 

 ment authority, and by finally establishing 

 geological horizons it has formed the basis of 

 all later geological work in this region. 



Dr. Owen had a large corps of scientific 

 assistants and through them left a strong 

 impress upon geological work in the Missis- 

 sippi Valley. Among them were Eichard 

 Owen and E. T. Cox, who worked later in 

 Indiana, A. H. Worthen in Illinois, Chas. 

 Whittlesey at Lake Superior and J. G. 

 Norwood in Kentucky. 



After five years of field and one of office 

 work, the report was published in two 

 quarto volumes, with a large colored geolog- 

 ical map, and a memoir on vertebrates by 

 Dr. Joseph Leidy. 



1847-1850. In this connection a brief 

 mention may be made of the survey of the 

 Lake Superior region, generally known as 

 the Foster and Whitney Survey, because, 

 although not carried on in the region under 

 consideration, it had indirectly considerable 

 influence on Western surveys. 



Congress in March, 1847, had passed a 

 law governing the sale of mineral lands in 

 the Lake Superior land district which pro- 

 vided that the Secretary of the Treasury 

 should cause a geological survey to be made 

 previous to the offering of the lands for sale. 



Dr. Chas. T. Jackson was appointed in 

 the spring of 1847 to execute the survey, 

 but resigned after two seasons' work, and 

 the completion of the work was confided 

 to J. W. Foster and J. D. Whitney, whose 

 final reports were submitted in 1850 and 

 1851. They were assisted in their geo- 

 logical work by S. W. Hill and Edward 

 Desor, the later an eminent Swiss geologist 

 who had come to this country with Agas- 

 siz ; while James Hall reported on their 

 fossils and made valuable geological contri- 

 butions to their final report. Whitney was 

 not again in government employ, but played 

 an important part in the development of 

 its mineral resources, by his volume on the 

 Metallic Wealth of the United States pub- 

 lished in 1854, in which the theoretical 

 views on ore deposits were far in advance 

 of any published in this country or Europe, 

 and which for many years was the only 

 scientific treatise on the metallic mineral 

 wealth of the country. He subsequently 

 (1859-60) served on the Geological Survey 

 of Wisconsin, making a special study of 

 its lead mines, and in 1860 organized the 

 State Geological Survey of California. 



1849. In 1849 Dr. John Evans, under the 



