18 
SPIRIT LEVELING. 
[bull. 185. 
Hook, and Old Point Comfort. Mean Gulf level is considered to be 
the same elevation as mean sea level. 
This adjusted precise-level net is considered to be the most reliable 
source of reference to mean sea level for the various local level lines 
which may touch upon it, until a sufficient number of additional pre- 
cise level circuits are formed by future work to make necessary another 
general adjustment and a closer approximation to mean sea level. 
No. 
Lines. 
1 Engineers' lines with Kern instruments; Coast and Geodetic Survey 
of 1899; water leveling on lakes, except between Cape Vincent and 
Oswego _ _ _ 
2 ! Wye levels run under the direction of the Engineers and Deep 
Waterways Commission, and the water levels between Cape Vin- 
cent and Oswego . . 
3 ! Geological Survey and Van Orden levels 
4 Leveling by the Pennsylvania Railroad 
5 Coast and Geodetic Survey, previous to 1899 
Weight, 
1^000 
z 
500 
z 
50 
z 
38 
z 
2, 500 
Z'- 
ATLANTIC SECTION OF TOPOGRAPHY. 
In this section, under the direction of Mr. H. M. Wilson, geographer 
in charge, spirit leveling was continued for the control of the regular 
topographic work executed during the year in various localities as 
listed below. In addition, leveling was carried on in the following 
localities during the year 1900; but as the field work in these locali- 
ties is not yet completed, or corrections are pending, the results will 
not be published until later : 
New York — Oneida, Lewis, Jefferson, Broome, Cortland, Chenango. 
Tioga, Tompkins, Madison, Steuben, Washington, Saratoga, and Ful- 
ton counties. 
Pennsylvania — Chester County. 
West Virginia — Wayne County. 
Ohio — Lawrence County. 
Kentucky — Greenup, Boyd, Carter, Lawrence, and Elliott counties. 
North Carolina — Yancey, Madison, Buncombe, McDowell, Mitchell, 
Burke, Caldwell, Catawba, Lincoln, and Gaston counties. 
South Carolina — York, Chester, Fairfield, and Richmond counties. 
Tennessee — Davidson and Franklin counties. 
Georgia — Whitfield, Murray, Gilmer, Fannin, Union, Towns, Haber- 
sham, White, and Lumpkin counties. 
