Report of the Superintendent ... Showing the Progress of the WorkU.S. Government Printing Office, 1920 |
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Alaska area covered azimuth bench marks established Block Island Block Island Sound Bureau Cagayan Islands Calif Cape Cape Mendocino charts Coast and Geodetic Coast Pilot Commanding Steamer completed connection depth determined double angles DIXON ENTRANCE drag eastward Engineers entrance fathoms feet field station fiscal G. S. Print Geodetic Survey geographic positions determined Hampton Roads Harbor horizontal measures hydrographic survey inshore July June 30 Key West launch Lighthouse located magnetic main scheme occupied Manila maps Marinduque miles of area miles run navigation necessary observatory obtained occupied for horizontal officer operation Pacific coast Palawan permanent bench marks photographs Point positions determined double primary triangulation progress reconnoissance reefs repairs River Romblon run while sounding San Francisco Sandakan scale season Shelikof Straits ship shoals shore line square miles stations in main stations occupied tidal Tide Tables tions topographic sheets topography traverse vessel vicinity Vinas River weather wire-drag
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32 ページ - Superintendent of the United States Coast and Geodetic Survey between 1894 and 1907.
35 ページ - State names and boundaries, principal rivers, capitals and largest cities in the different states, are the only information otherwise embodied. The map is of special interest from the fact that it is based on the same system of projection as that which was employed by the armies of the allied forces in the military operations in France. To meet those requirements and at the request of the Army, special publications were prepared by the Coast and Geodetic Survey.
35 ページ - If at any point the scale along the meridian and the parallel is the same (not correct, but the 'same in the two directions) and the parallels and meridians of the map are at right angles to one another, then the shape of any very small area on the map is the same as the shape of the corresponding small area upon the earth. The projection is then called orthomorphic (right shape).
36 ページ - The value of the new outline map on the Lambert projection can best be realized when it is stated that throughout the larger and most important part of the United States, that is, between latitudes 30J^° and 49°, the maximum scale error is only one-half of one per cent.
86 ページ - Atlantic City was chosen as it is characteristic of so much of the coastal plain territory of the Atlantic coast. This project was essentially experimental in character, but developed into one of practical value, as the photographs are being used in a revision of the charts of the New Jersey coast. This work was done in cooperation with the Air Services of the Army and Navy. Both land and sea planes were used, and in addition several photographs were made from a dirigible. Three types of mapping...
86 ページ - type, Kl, and Trilens. An officer of the survey kept in close touch with the work and furnished the ground control, constructing special targets in some cases. A mosaic was constructed by members of the Air Service of the Army, using the photographs made with the Kl mapping camera. These were taken at an altitude of 7,000 feet, using a lens of 10 inch focal length, with a resulting scale of about 1 :8,000.
43 ページ - ... where industry has preceded surveys and dangers have been found by vessels striking them or where industry has established itself and demands a local survey. The equipment for these surveys is so limited that no definite plan can be laid for their ultimate completion or for the issuing of charts that will be guides to all parts of Alaskan waters. The making of surveys and supplying of reliable charts for the urgent needs of Alaska is a question of the number of modern surveying vessels and wire-drag...
62 ページ - ... the work required to bring them up to date has been postponed, as the need for resurveys has been more urgent farther south. Up to a few years ago the offshore surveys from Cape Hatteras to the Florida Reefs were almost unbelievably deficient. This condition is being remedied as rapidly as possible, and between Winyah Bay, SC, and St. Augustine, Fla., the offshore work out to the Gulf Stream is complete. .It is important that this work be extended both north and south from its present limit as...
62 ページ - In surveying practice the uncertainties which exist in the use of this method in ordinary navigation have been reduced by stopping at intervals to observe currents and wind pressure and by starting from and returning to well-fixed positions.
62 ページ - Kay entrance to Chesapeake Bay. — From Delaware Bay entrance to Chesapeake Bay there is a succession of shoals and banks. Many of these are buoyed so that moderate-draft vessels may pass inside of them. In certain regions it is of the highest importance that the survey should be correct and kept up to date. At only one place has a comprehensive survey been made, and this was the investigation of a reported shoal.