ADVERTISEMENT. IX 
14. New Tests of Pumps and Water-Lifts used in [irrigation, by 0. P. Hood. L898. 8°. 9] pp. 1 pi. 
15. Operations at River Stations, 1897, Parti. 1898. 8°. LOOpp. 
16. Operations at River Stations, 1897, Part II. 1898. 8°. 101-200 pp. 
17. Irrigation near Bakersfield, California, by C.E.Grunsky. 189<s. 8°. 96 pp. 16 pi. 
18. Irrigation near Fresno, California, by C.E.Grunsky. 1898. 8°. 94 pp. 11 pi. 
19. Irrigation near Merced, California, by C.E.Grunsky. 1899. 8°. 59 pp. 11 pi. 
20. Experiments with Windmills, by T. O. Perry. 1899. 8°. 97 pp. 12 pi. 
21. Wells of Northern Indiana, by Frank Leverett. 1899. 8°. 82 pp. 2 pi. 
22. Sewage Irrigation, Part II, by George W. Rafter. 1899. 8°. 100 pp. 7 pi. 
23. Water-right Problems of the Bighorn Mountains, by Elwood Mead. 1899. 8°. 62 pp. 7 pi. 
24. Water Resources of the State of New York, Part I, by G. W. Rafter. 1899. 8°. 99 pp. 13 pi. 
25. Water Resources of the State of New York, Part II, by G.W. Rafter. 1899. 8°. 101-200pp. 12pl. 
26. Wells of Southern Indiana (Continuation of No. 21), by Frank Leverett. 1899. 8°. 64 pp. 
27. Operations at River Stations for 1898, Part I. 1899. 8°. 100 pp. 
28. Operations at River Stations for 1898, Part II. 1899. 8°. 101-200 pp. 
29. Wells and Windmills in Nebraska, by Erwin H. Barbour. 1899. 8°. 85 pp. 27 pi. 
30. Water Resources of the Lower Peninsula of Michigan, by Alfred C. Lane. 1899. 8°. 97 pp. 7 pi. 
31. Lower Michigan Mineral Waters, by Alfred C. Lane. 1899. 8°. 97 pp. 4 pi. 
32. Water Resources of Puerto Rico, by Herbert M. Wilson. 1899. 8°. 48 pp. 17 pi. 
33. Storage of Water on Gila River, Arizona, by Joseph B. Lippincott. 1900. 8°. 98 pp. 33 pi. 
34. Geology and Water Resources of SE. South Dakota, by J . E. Todd. 1900. 8°. 34 pp. 19 pi. 
35. Operations at River Stations, 1899, Part I. 1900. 8°. 100 pp. 
36. Operations at River Stations, 1899, Part II. 1900. 8°. 101-198 pp. 
37. Operations at River Stations, 1899, Part III. 1900. 8°. 199-298 pp. 
38. Operations at River Stations, 1899, Part IV. 1900. 8°. 299-396 pp. 
39. Operations at River Stations, 1899, Part V. 1900. 8°. 397-471 pp. 
TOPOGRAPHIC MAP OF THE UNITED STATES. 
When, in 1882, the Geological Survey was directed by law to make a geologic map of the United 
States, there was in existence no suitable topographic map to serve as a base for the geologic map. 
The preparation of such a topographic map was therefore immediately begun. About one-fifth of 
the area of the country, excluding Alaska, has now been thus mapped. The map is published in 
atlas sheets, each sheet representing a small quadrangular district, as explained under the next head- 
ing. The separate sheets are sold at 5 cents each when fewer than 100 copies are purchased, but 
when they are ordered in lots of 100 or more copies, whether of the same sheet or of different sheets, 
the price is 2 cents each. The mapped areas are widely scattered, nearly every State being repre- 
sented. About 900 sheets have been engraved and printed; they are tabulated by States in the 
Survey's " List of Publications," a pamphlet which may be had on application. 
The map sheets represent a great variety of topographic features, and with the aid of descriptive 
text they can be used to illustrate topographic forms. This has led to the projection of an educa- 
tional series of topographic folios, for use wherever geography is taught in high schools, academies, 
and colleges. Of this scries the first two folios have been issued, viz: . 
1. Physiographic types, by Henry Gannett, 1898, folio, consisting of the following sheets and 4 pages 
of descriptive text: Fargo (N. Dak. -Minn.), a region in youth; Charleston (VV. Va.), a region in 
maturity; Caldwell (Kans.), a region in old age; Palmyra (Va.), a rejuvenated region; Mount Shasta, 
(Cat.), a young volcanic mountain; Eagle (Wis.), moraines; Sun Prairie (Wis.), drumlins; Donald- 
sonville (La.), river flood plains; Boothbay (Me.), a fiord coast: Atlantic City (N. J.), a barrier-beach 
coast. 
2. Physiographic types, by Henry Gannett, 1900, folio, consisting of the following sheets and 11 pages 
of descriptive text: Norfolk (Va.-N. O), a coast swamp; Marshall (Mo.), a graded river; Lexington 
(Nebr.), an overloaded stream, Harrisburg (Pa.), Appalachian ridges; Poteau Mountain (Ark.-Ind. 
T.), Ozark ridges; Marshall (Ark.), Ozark Plateau; West Denver (Colo.), hogbacks; Mount Taylor 
(N.Mex.), volcanic peaks, plateaus, and necks; Cucamonga (Cal.), alluvial cones; Crater Lake special 
(Oreg.) , a crater. 
GEOLOGIC ATLAS OF THE UNITED STATES. 
The Geologic Atlas of the United States is the final form of publication of the topographic and 
geologic maps. The atlas is issued in parts, or folios, progressively as the surveys arc ex t ended, and 
is designed ultimately to cover the entire country. 
Under the plan adopted the entire area of the country is divided into small rectangular districts 
(designated quadrangles) , bounded by certain meridians and parallels. The unit of survey is also the 
unit of publication, and the maps and descriptions of each rectangular district are issued as a folio of 
the Geologic Atlas. 
Each folio contains topographic, geologic, economic, and structural maps, together with textual 
descriptions and explanations, and is designated by the name of a principal town or of a prominent 
natural feature within the district. 
