Oklahoma. In cooperation with the Territory, one 15-minute quadrangle, in Lincoln County, was controlled by locating 24 points by triangulation, and one quadrangle in Pottawatomie County was controlled by means of 72 miles of primary traverse. The field work was done by H. H. Hodgeson.

Oregon. In cooperation with the State the portion of the Blalock Island quadrangle that lies within Morrow County was controlled by 4 triangulation points located by C. F. Urquhart and A. I. Oliver. The Mount Hood Special area, in the Bull Run National Forest, was controlled by 9 triangulation points located by Mr. Urquhart.

Washington.-An area of 3,000 square miles in Benton, Franklin, Klickitat, and Wallawalla counties was controlled by means of 27 triangulation points located by Messrs. Urquhart and Oliver.

OFFICE WORK.

The office computations of triangulation, primary traverse, and adjustment of level circuits were continued in charge of S. S. Gannett until the reorganization of the topographic branch on March 19, when E. M. Douglas was placed in charge. The results of primary triangulation and primary traverse in 27. States were summarized and published in Bulletin No. 310. The triangulation and leveling plats of all States were brought up to date, as well as the card catalogue of triangulation and primary-traverse stations. The preparation of triangulation and leveling data for chiefs of field parties and in reply to requests of persons not connected with the Survey required the time of a considerable portion of the office force.

During the year the following results were computed by members of the topographic branch, detailed from time to time for office computing:

EASTERN DIVISION.

Alabama. For the control of the Coalville quadrangle, in Shelby County, 370 latitudes and departures and 36 geographic positions were computed. Level circuits in the same area were adjusted. For that portion of the Columbus, Ga., quadrangle which lies within Russell County, Ala., 125 latitudes and departures and 23 geographic positions were computed..

Florida. For the control of the soil survey map of Jefferson County, 930 latitudes and departures and 105 geographic positions were computed.

Georgia. For the Columbus, Eatonton, Milledgeville, and portions of adjoining quadrangles, 1,530 latitudes and departures and 217 geographic positions were computed. The office computation of the precise-level line from Macon to Milledgeville was completed.

Illinois. Latitudes and departures to the number of 1,671 and 369 geographic positions were computed for the control of 7 quadrangles in the counties of Franklin, Hamilton, Saline, Williamson, Lake, Perry, and Jo Daviess. Level circuits in the same area were adjusted and the office computation of the precise-level lines Duquoin to Shawneetown and Olney to Champaign was completed.

Indiana. For the Bloomington, Saline City, and Terre Haute quadrangles, in Monroe, Morgan, Clay, Owen, Parke, and Vigo counties, 1,229 latitudes and departures and 194 geographic positions were computed. The office reduction of the precise-level line Mitchell to Bedford was also made.

Kentucky. The geodetic positions of 8 triangulation stations in Breathitt, Knott, and Pike counties, and 2,105 latitudes and departures and 160 geographic positions in Wayne, Franklin, Owen, Caldwell, and Crittenden counties were computed. Level circuits were adjusted in the Frankfort, Lockport, Burnside, Monticello, and Clay quadrangles. The office reduction of the precise-level lines from Georgetown to Louisville and from Lexington to Jackson was completed.

Louisiana. For the Winnfield 15-minute quadrangle and for the remaining part of Winn Parish 2,092 latitudes and departures and 162 geographic positions were computed. Latitudes and departures to the number of 460 and 110 geographic positions in Acadia, Iberia, Lafayette, St. Mary, St. Martin, and Vermilion parishes were computed and office reduction of the precise-level line through the same parishes was made.

Maine. The office reduction of the precise-level line in Cumberland and Oxford counties was made, and circuits of primary levels in the Lewiston and Poland quadrangles were adjusted.

Maryland.-Primary-level circuits were adjusted for Montgomery and Carroll counties.

Minnesota. The office computation of the precise-level line in the ceded lands of the Chippewas, Red Lake County, was completed, and circuits of primary levels in the same area were adjusted.

Kansas-Missouri.-For the Leavenworth quadrangle, in Platte County, Mo., and Leavenworth County, Kans., and the Easton quadrangle, in Jefferson and Atchison counties, Kans., 580 latitudes and departures and 90 geographic positions were computed. Primarylevel circuits in the same area were adjusted.

Missouri-Kansas-Oklahoma.-Primary-level circuits in No. 2 County, Okla., Newton and McDonald counties, Mo., and Cherokee County, Kans., in the Wyandotte 30-minute quadrangle, were adjusted, and 690 latitudes and departures and 56 geographic positions were computed.

New Hampshire-Vermont.-The office reduction was made of the precise-level line in Belknap, Carroll, and Grafton counties, N. H., and Windsor County, Vt. Primary-level circuits in the Winnepesaukee quadrangle, New Hampshire, were adjusted.

North Carolina-South Carolina.-Primary-level circuits were adjusted in the Gaffney and Kings Mountain quadrangles, and 1,060 latitudes and departures and 144 geographic positions, controlling these quadrangles, were computed.

Ohio. For 12 quadrangles in the counties of Hocking, Jackson, Vinton, Fairfield, Pickaway, Carroll, Coshocton, Holmes, Stark, Tuscarawas, and Wayne, 2,044 latitudes and departures and 332 geographic positions were computed. The office reduction of the precise-level lines Chillicothe to Portsmouth, Columbus to Uhrichsville, and Ottawa to Tontogany was made, and primary-level circuits in the following counties were adjusted: Franklin, Fairfield, Ross, Pike, Scioto, Defiance, Henry, Lucas, Paulding, Harrison, Jefferson, Carroll, Columbiana, and Portage.

Pennsylvania. The geodetic positions of 17 triangulation stations, 745 latitudes and departures, and 100 geographic positions of primary-traverse stations in Bedford, Butler, Adams, Cumberland, Indiana, and Jefferson counties were computed. Level circuits in parts of the same counties were adjusted.

Tennessee. Computations of 2,481 latitudes and departures and 372 geographic positions were made in the Franklin, Jackson, and Woodbury quadrangles. The office reduction of the precise-level line Nashville to Woodbury was completed.

Virginia. The geodetic positions of 4 triangulation stations in Botetourt and Rockbridge counties were computed, and the office reduction of the precise-level line Buchanan to Alleghany station was completed.

West Virginia. The geodetic positions of 3 triangulation stations in Barbour and Randolph counties were computed, and primarylevel circuits in Mason, Jackson, Putnam, and Roane counties were adjusted.

WESTERN DIVISION.

Arizona.-The office reduction of the precise-level line from the Arizona-New Mexico line to Tucson was made, and all level circuits in the Territory were readjusted and the elevations of bench marks reduced to mean sea-level datum.

California. The geodetic positions of 42 triangulation stations in Contra Costa, Sacramento, Solano, San Joaquin, and Yolo counties were computed. All circuits of levels in the State were adjusted, the elevations of bench marks were reduced to mean sea level, and the results were prepared for publication as a bulletin.

Colorado. The geodetic positions of 6 triangulation stations in Larimer County and of 18 stations in Archuleta, Hinsdale, and La Plata counties were computed, and level circuits in the same counties were adjusted.

Montana. The geodetic positions of 12 triangulation stations in Dawson County were computed, and level circuits in Fergus County were adjusted.

New Mexico. The geodetic positions of 26 triangulation stations in Rio Arriba and San Juan counties were computed, and level circuits in the same counties were adjusted. The office reduction of the precise-level line from Deming to the Arizona line was completed. Nevada. The geodetic positions of 14 secondary triangulation points in White Pine County were computed.

Oklahoma. The geodetic positions of 15 triangulation points and the geographic positions of 63 primary-traverse points in Lincoln and Pottawatomie counties were computed, and primary-level circuits in the same counties were adjusted.

Oregon. The geodetic positions of 9 triangulation stations controlling the Mount Hood Special quadrangle were computed.

Oregon-Washington. The geodetic positions of 31 triangulation stations in Morrow County, Oreg., and Benton, Klickitat, Franklin, Yakima, and Wallawalla counties, Wash., were computed, and level circuits in the same area were adjusted.

Wyoming.-Level circuits throughout the State were readjusted, elevations of bench marks corrected to mean sea level, and the results arranged for publication.

SECTION OF INSPECTION OF TOPOGRAPHIC SURVEYING AND MAPPING.

During the field season inspection of topographic mapping, complete or in progress, was carried on by John H. Renshawe in the eastern part of the United States. The purpose of this work was the maintenance of uniformity of style and system in the expression of topographic features. All topographic parties in States east of Mississippi River were visited and given instruction.

During the office season careful attention was given to the final drawing of map sheets, for the purpose of eliminating personal characteristics and errors of expression. Attention was also given to the preparation of material for revision of the base map of the United States.

SECTION OF INSTRUMENTS AND TOPOGRAPHIC RECORDS.

During the year the usual custom of making a general overhauling of all instruments was continued. This work was done in the shop of the Survey, except when extensive repairs, beyond its capacity,

were required, when the instruments were sent to the makers. Purchases were made from time to time to cover losses sustained by wear and tear in the field. Ten telescopic alidades, with special stadia attachment, were bought, as the experiments of the previous year proved that this attachment was most useful. Experiments were continued with solar alidades, with the view of adapting an instrument of this class to topographic work.

The filing of the original records under the existing card system was continued. The number of such pieces filed was about 1,500, comprising triangulation, level, and topographic notebooks and plane-table sheets. In addition, about 100 pieces of miscellaneous material were catalogued for filing.

DIVISION OF GEOGRAPHY AND FORESTRY.

The division was continued under the direction of Henry Gannett. The principal results were as follows:

The revision of the three-sheet map of the United States on a scale of 1:2,500,000 was continued and good progress was made.

The preparation of sheets, as part of the world-map scheme, on a scale of 1: 1,000,000 was continued. Seven such sheets have been projected, and all available surveyed material has been added to them. Separate maps of Wyoming, Utah, Colorado, Arizona, New Mexico, West Virginia, Virginia, Maryland, and Delaware have been drawn, embodying all available surveyed material.

Preparation of maps of the national forests has been continued in the form of township plats. These plats were at first made on a scale of 2 inches to the mile, and each township was published as an individual map. In order to meet better the needs of the Forest Service the scale was afterwards changed to 1 inch to the mile, and six townships are published together on an atlas sheet, on which is shown the land, timber, and alienation classification by color and by symbols. Additions to national forests which had been completed necessitated many changes in the manuscripts.

The preparation of "The areas of the United States, the States, and the Territories," published as Bulletin No. 302, which is the result of cooperation between the Census Office, the General Land Office, and the Geological Survey, is an attempt to bring the figures of areas into accord.

The "Manual of topographic methods" was prepared and published as Bulletin No. 307.

A list and descriptions of 100 atlas sheets illustrating topographic forms was prepared and published.

The preparation of gazetteers of New York and California was well advanced.