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Tables, which, prepared annually in advance of the year for which they are intended, give the daily high and low values of the tidal phenomena for each day of the year for every port in the United States and for all the leading ports of the world; in the 21 volumes of the Coast Pilot and Sailing Directions, and in its weekly notices to mariners, published in cooperation with the Bureau of Lighthouses. These publications supply such comprehensive, accurate, and detailed information concerning the navigation of our coasts and the approaches to our harbors that, save in the case of certain little-frequented sections of Alaska and the Philippines, and certain channels where storms and currents produce constant changes, it may be truthfully claimed that in American waters the mariner is afforded an unrivaled opportunity for the safe navigation of his vessel.
In addition to the foregoing the Survey issues a great variety of publications recording the researches of its officers as well as the results of its surveys. These are distributed free to schools, scientific institutions, libraries, and individuals particularly interested in them.
The first survey of the Atlantic, Gulf, and Pacific coasts of the mainland of the United States, except in the case of Alaska, has been completed, but the ceaseless changes due to the operation of the tides; to the alterations in the conditions of our great river systems, resulting from the subjection to cultivation of the interior of our continent; to the demands for change and improvement that are a consequence of the scale upon which modern works for meeting the demands of trade and commerce are planned; to the requirements of leviathans that are now considered essential for both the necessities of commerce and national defense; to the needs of the rapidly increasing fleets of motor boats, and, lastly, the secular results of continental upheaval and subsidence, necessitate revision of surveys from time to time.
On the Atlantic and Gulf coasts this work of revision and addition requires the employment of two steamers of the Survey, two schooners, and several chartered launches; another small steamer, which was especially designed for the work in which it is engaged, is necessary for the surveys and examinations which have to be made to keep the information in the Coast Pilot volumes for the Atlantic and Gulf coasts accurate and timely.
Along the Pacific coast four steamers and two large launches are required to meet the pressing demands for accurate surveys in Alaskan waters. In the winter season one of the steamers from this fleet is engaged in surveys in Hawaiian waters and the other steamers are on duty for chart revision and necessary resurveys to meet the constantly growing importance of the coast from the Strait of Juan de Fuca to San Diego.
The acquisition of Porto Rico, Hawaii, and the Philippines increased tremendously the responsibilities of the Survey. Porto Rico, although one of the oldest Spanish possessions in the New World, was so poorly charted that the Sailing Directions of the British Admiralty cautioned navigators to make an allowance of from 4 to 5 miles in approaching its shores. One of the first results of the work undertaken by the Coast and Geodetic Survey was the development of the land-locked harbor of Jobos, and this was followed by the development which first made available for commerce other harbors on the south and west coasts.
In the Philippines, on a larger scale, was presented the spectacle of a country lavishly endowed by nature with her richest gifts, islands with lands of exuberant fertility, and mountains seamed with precious veins of minerals and vestured with forests of the most magnificent woods almost impenetrably sealed against the world's uses by the indifference of its masters to surveying and charting its waterways and shores. The archipelago comprises 3,141 islands and islets, and as there is no point in the group distant more than 60 miles from the sea the importance of correct charting of its vast system of waterways is self-evident. This duty was one of the first undertaken in the islands by the United States, and in December, 1900, a suboffice of the Coast and Geodetic Survey was opened in Manila, simultaneously with which astronomic, topographic, and hydrographic parties began operations, which have been continued with the greatest diligence and have shown the most gratifying results. The importance of the work in the Philippines was almost instantly recognized by the insular government, which, from the beginning, most generously cooperated with the national authorities. The field results receive their preliminary discussion and are prepared for earuest possible publication in Manila. A large force of native draftsmen is employed in the Manila office in the preparation of chart drawings, which are engraved and printed in Washington, D. C.
A very important operation of the Survey is the determination of the exact elevations of standard points throughout the country by lines forming a network of refined levels, which furnishes a connection for securing the most useful results from the thousands of miles of levels run for works of public improvement.
The magnetic surveys, which at sea and on shore are so essential for the perfection of charts and so important for the property and political interests of this country, where the magnetic needle has been so generally used in determining property outlines and boundary lines, form a very important part of the activities of the Survey.
The character of the operations necessary for charting the great coast line of the United States demanded from the first the qualifications looked for in the technical experts to whom are intrusted boundary and delimitation work of the highest importance, and both the States and the National Government call on the Coast and Geodetic Survey for the execution of many of the more important projects of this character. The requests of the States of New York, Maryland, and Delaware for the detail of officers to supply technical direction for political and economical surveys in those States are examples of the varying demands to which the splendidly trained and equipped technical force furnish adequate response.
The Superintendent, as Commissioner on the part of the United States, is charged with surveying and marking the southeastern boundary of Alaska from Portland Canal to Mount St. Elias, and of the meridianal boundary from Mount St. Elias to the Arctic Ocean, the survey parties engaged in the field work facing hardships, privations, and dangers known only to the most intrepid of explorers. Under his direction other parties are engaged in the re-marking and additional boundary surveys required along the forty-ninth parallel of latitude, in Montana, North Dakota, and Minnesota. On the northeastern boundary parties under his direction are making surveys for the revision of the boundary in the St. John and St. Croix Valleys.
An officer of the Survey is detailed as a member of the Mississippi River Commission.
While the valuable office equipment of the Bureau can not show a picturesqueness comparable with that noted in a consideration of the duties of the field section with its personnel spread from the Antilles to the China Seas and from Bering Sea to waters within 5 degrees of the Equator, the variety of its tasks are as great and its operations as interesting and instructive. In addition to the administrative divisions there are the Computing, Chart Construction, Instrument, and Tidal Divisions.
In the Computing Division are discussed with the highest mathematical refinement the observations made in the field, the results being prepared for their final publication and utilization.
The Chart Construction Division comprises the drawing, engraving, electrotype, photograph, and printing sections, all engaged in the construction, maintenance, and publication of charts. The drawing section assembles and compiles all chart information received, including the results of the topographic and hydrographic parties, harbor improvement surveys of the Army Engineers, surveys by local engineers, additions and changes in lights and buoys, and newly discovered rocks and other dangers. From this information new chart drawings are prepared for engraving or photolithography and old charts are brought up to date. The engraving section engraves the chart drawings on copper plates and makes the changes required on the plates. The electrotype section duplicates the engraved copper plates previous to printing, so that worn plates can be replaced by new ones. The photograph section makes negatives for those charts published by photolithography, makes photographic copies of original surveys required by other departments and the courts, and etches on copper some of the new charts. The printing section prints from copper plates and by photolithography over 140,000 charts a year.
In the Instrument Division have been initiated types of instruments that are now adopted by the national European surveys, one of its late achievements being the construction of the most effective tidal predicting machine in existence. This machine takes into account 37 of the tidal influencing components, producing a year's record of predictions of all the daily high and low waters for a port in less than ten hours, an undertaking not possible by the direct computation of 100 computers.
In the Tidal Division are discussed the tidal phenomena on such a scale that the Tide Tables of the Survey, published annually in advance, furnish the mariner with the values of the high and low tides at 3,270 ports selected from all over the world and covering every region of any value to commerce.
A study of the annual report of the Superintendent of the Survey will disclose an account of activities which are of the highest value to the mariner, the hydrographer, the surveyor, the engineer, the landowner, and the physicist, and a record which, for the practical needs of commerce and the contribution which the United States in common with other first-class powers is making to the knowledge of the dimensions and configuration of the globe we live on, is worthy of the honorably distinguished name which has so long been borne by this the oldest bureau of applied science under the Government.
A more extended description of the organization and functions of the Survey will be found in the pamphlet entitled "The Work of the Coast and Geodetic Survey," which those interested may obtain on application.
Superintendents of the United States Coast and Geodetic Survey, with dates of service.
LAW PERTAINING TO THE UNITED STATES COAST AND GEODETIC
[As modified by acts of February 14, 1903, and March 4,1913.]
coast authorised' The President is authorized to cause a survey to be ij.'s., mi. 'taken of the coasts of the United States, in which shall be designated the islands and shoals, with the roads or places of anchorage, within twenty leagues of any part of the shores of the United States; and also the respective courses and distances between the principal capes or headlands, together with such other matters as he may deem proper for completing an accurate chart of every part of the coasts.
yondr2o leagues The President may also cause such examinations and from shore. observations to be made with respect to Saint George's R. s., 4sst. BanJ^ and to any other bank, or shoal, and the soundings and currents, although beyond the distance of twenty leagues from the shore to the Gulf Stream, as he may deem especially subservient to the commercial interests of the United States. ptoycdhodsem- AH appropriations made for the work of surveying the K. s.', 46ss. coast of the United States shall be expended in accordance with the plan of re-organizing the mode of executing the survey which has been submitted to the President by a board of officers organized under the act of March three, eighteen hundred and forty-three, chapter one hundred. Ar^a^NaVy Tne President shall carry into effect the plan of the officers. board, as agreed upon by a majority of its members;
''' and shall cause to be employed as many officers of
the Army and Navy of the United States as will be compatible with the successful prosecution of the work1; the officers of the Navy to be employed on the hydrographical parts, and the officers of the Army on the topographical parts of the work; and no officer of the Army or Navy shall receive any extra pay out of any appropriations for surveys.
bdo'ksVeetcto am! The President is authorized, in executing the provisions to employ per- of this Title, to use all maps, charts, books, instruments, SOXRis.,468s. and apparatus belonging to the United States, and to direct where the same shall be deposited, and to employ all persons in the land or naval service of the United States, and such astronomers and other persons, as he shall deem proper.
pay^^mp'ioy^ Scientific and other employees of the United States eeVar / * Coast and Geodetic Survey, while employed outside of sm"istt). <a< the District of Columbia, are hereby authorized to make assignments of their pay, under such regulations as the Secretary of Commerce may prescribe. leave'o'fVteanM6 The Secretary of Commerce, at his discretion, may staler'1909(S*nereafter grant to officers of the field force of the ''"' Coast and Geodetic Survey on duty in the Philippine Islands, at one time the whole or any portion of the annual leave accrued and unused during a period of three years.
1 By reason of changed conditions, this provision has become inoperative.