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be preferred to that of deferring the publication until the close of the survey.

With the present report will be presented a list of geographical positions, 3,240 in number, derived from the preliminary calculations of the work. The degree of accuracy which has been reached in the different sections will be explained when considering the details. It will be found that improved methods of determining the latitudes by observation have been employed; that the various methods which astronomy and geodesy furnish for determining longitudes have been applied; and that, in addition to the usual ones, we have introduced for the first time, as part of a geodetic work, the determination of difference of longitude by the telegraph. This list will receive revision from time to time; but its publication now will afford very useful data to geographers, surveyors, and even to astronomers. It will be followed by others relating to magnetism and the tides. This is a new feature in the annual report, and, with the extension of the number of sketches, will add materially to the interest which it would have as a report of progress. .

For the development of the plans of office work as facilities have been afforded by the additional appropriations, the urging to completion this list of geographical positions, and the increased rapidity of publication, the coast survey is indebted mainly to the zeal and industry, guided by knowledge and intelligence, of Brevet Major I. I. Stevens, of the corps of engineers, in acknowledging which, in connexion with the remarks on the speedy publication of the results of the survey, I feel that I am doing simply an act of justice...

The organization under which the survey is conducted has been so repeatedly explained and approved, that it needs merely a passing notice. In 1843, a board was convened, under authority and by direction of Congress, embodying in its constitution all the experience which could be furnished by the history of the survey, by consisting of civilians and officers of the navy who had served in it, and officers of the army who had served in it, or were professionally conversant with its details.

This board provided for the continuation of the organization which both reasoning and experience found to be the most effective, combining the scientific and practical acquirements of civilians, officers of the army, and officers of the navy, in the work. The survey was recognised as primarily for the benefit of commerce, but having important connexions with defence;- providing for a permanent nucleus of civilians, and for the detail of officers of the army and navy, necessarily varying from time to time in numbers and persons as the exigencies of the military or naval service prevailed over the wants of the survey ;recognising on the one hand that this branch of applied science was a profession requiring long and careful study, and on the other that the practical skill of the naval officer, or the West Point education of the army officer, might most usefully contribute to the progress of the survey;—not excluding the man of science from one of the highest works of applied science which his country has engaged in, nor the army or navy officer from an appropriate sphere of usefulness;—not exposing the work to the contingencies of being arrested by even an alarm of war, nor of excluding the officer of the army or navy from a position in it while his services could be spared from other duty ;-not organizing a permanent corps to execute a temporary work, nor yet making the survey a mere school by which all its operations would bear upon them the stamp of the beginner ;-combining, as is appropriate to our institutions and our time, the knowledge and experience, wherever to · be found, necessary to render its execution creditable to the character of the country. Such an organization could not exist under either the Navy or War Department, and, as most appropriate to a work of commerce, was placed under the direction of the Treasury Department.

Circumstances have forced the closest scrutiny of the organization, progress, results, economy-in short, of every particular relating to the coast survey; and it must be gratifying to the Executive and legislature, who have done so much for its advancement, to find the uniform approval from the highest authorities, both scientific and practical, at home and abroad, which this scrutiny has developed. In this result is to be found the best guaranty, that, if this fostering care is continued, the survey of the coast will be properly completed in a reasonable time, and with a reasonable outlay of means. Within the year, the Geographical Societies of London, Paris, and Berlin, have given the most unequivocal evidence of their interest -in, and approval of, the character of the coast survey. :

In former reports I have compared the results of the survey on different scales of appropriation with each other. At first, on presenting the plan for its enlargement, it was difficult to convince those upon whom the increase depended that economy would be produced. Each step rendered this less difficult by furnishing positive data in figures. The present scale presents for the Atlantic coast a result of three and a half to one, with an expenditure of less than two to one. (See report of 1850.) So, also, it turns out that the operations which conduce to the essential scientific accuracy of the work are not those which tell most in the sum total of the expenditures; and that while, without those, the character of the work on land would be unworthy of the country, and the hydrography mere reconnaissance, they do not double the cost of the land parties. I have gone into these computations in the report of *1848, and have shown that the cost of measurement of base lines, the astronomical work, and the triangulation, was less than the cost of the topography which was essential to the delineation of the coast; while, in reference to the accuracy of the work, their importance cannot be over-estimated. An examination of the geodetic method, as compared with the mode in use in the Land Office of the United States, showed an aggregate cost per lineal mile for all operations, without the cost of drawing, less than the maximum allowed for the land surveys; and with the finished drawings, a cost but little exceeding il-($11 25 per lineal mile. See report of 1848.) As compared with the cost of foreign surveys, the Secretary of the Treasury has shown (see repor, Senate Doc., Ex. No. 26, 1849) that this work has largely the advantage in point of economy—an advantage which I apprehend woudl have been lost to it, if, as in some of the organizations abroad, a permanent corps, deriving its emolument from other service, and only incidentally employed in this, had been organized to execute it; or if intrusted to a body composed entirely of changing elements, not devoted professionally to scientific pursuits.

The lowest estimate which I can make of the progress of the work on the coast of the Atlantic and Gulf of Mexico, is, that at the commencement of this fiscal year more than three-eighths had been completed. This estimate is made from a careful examination of the progress in the different sections. The shore-line to be surveyed has been estimated from the best data which could be obtained; and it is easy in every section, except those where the work has been introduced very recently, to estimate with considerable accuracy its rate of advance. A general reconnaissance has been begun which will much facilitate this calculation, and enable us to introduce the elements of facility or difficulty of survey into the estimates for the time of completion of the different sections. The greater expenditure necessary for the maintenance of each party in the southern sections must enter also into such an estimate, if the total amount to be expended is considered as final. In some portions of the operations, as for example the topography, the smaller number of details necessary in the southern sections diminishes the time required for the survey of a given"extent of shore-line, or a given area; but the expenditure in the whole is considerably greater than in the others. The present rate of annual progress is certainly between four and six per cent. of the remaining shoreline.

The time when the work is to be completed, I am aware, is of less consequence than the manner in which it is done. If executed by any but the best methods, it will undoubtedly be done over at some future day. We have not yet found a portion of the coast to which the geodetic method is inapplicable. There may be such, and then we shall not be without resource, but at present we are not compelled at any point to abandon the most exact methods. The mountains of Maine, New Hampshire, and Massachusetts, and the hills from Maine to Maryland, afford every facility for triangulation; the wide expanse of Chesapeake bay in Maryland and Virginia, and of Albemarle and Pamplico sounds in North Carolina; the sea-islands and passages of South Carolina and Georgia; the keys and main of Florida, Mobile bay, and the islands off the coast of Alabama, Mississippi and Louisiana; the bays and prairies of Texas; the bare hills of California; the hills and sounds of Oregon, are all characteristic features of the several parts of the coast, requiring only to be recalled to the mind to indicate the easy application of the geodetic method to a survey of the coast. The points being well determined and marked on the land, and the shore-line traced, the hydrography is readily executed with the requisite nicety.

Every part of these operations must go on according to a system, or the result fails in completeness, or in economy. This is secured by a general plan of operations, the details of which are submitted by the Superintendent to the Treasury Department, annually; and which, when approved, are executed according to instructions given as to the scientific details by the Superintendent. The modes employed are thus as uniform as can be obtained from the operations of different individuals. The plan of distribution given in Appendix No. 1, is in execution of the “Directions” thus approved by the Secretary of the Treasury in March, 1850, and 1851. At the close of each season,

the assistants report the results of their work, which are embodied in the notices of the several operations in the annual report of the Superintendent. .

The resolution of Congress, under which the plan of organization of 1842 was drawn up, required that as many officers of the army and navy as practicable should be employed: the army officers on the land part, and the navy officers on the water part, of the work. The number of army officers was gradually increased from 1844 to 1848, when it had reached fourteen, namely, five staff and nine line officers. These were necessarily removed, with but few exceptions, on the breaking out of the Mexican war; and but for the connexion of civilians with the survey, trained to its operations, the land work would have ceased. Informal notice was given at one time that there might be a necessity for withdrawing also the officers of the navy; but, as the war was not a maritime one, we did not suffer that loss. Soon after the war closed, application was made for the detail, again, of officers of the army, which was met by a request that formal action might be postponed until the regiments were at the posts assigned them. This was in 1848. In 1849 the application was again made and declined, and in 1850 was renewed; and from time to time officers have been detailed until the number now attached to the survey is eleven-namely, four from the engineers and topographical engineers, and seven from the line; and two applications remain not finally disposed of. The names and rank of these officers, and dates of their detail, are given in the Appendix No. 2. Their services have already told in the execution of the operations of the past season, and will be of still further value in those of the next, as they all obtain the necessary experience in the practical operations of the survey now possessed by some.

The number of hydrographic parties has been increased under the injunction of the law, as their services could be rendered available. It now consists of ten parties, of which four are occupied in sections where the seven months which include the summer are most profitable for work afloat; one where the work is done in the autumn and spring; four where the seven months including the winter constitute the best working season; and one is employed during the greater part of the year. This past summer, two of the parties have been transferred from southern sections, at the termination of their working season, to do duty for a time in a more northern one. The average number of officers in each party during the season, afloat, is five. On closing their work afloat, three of each party are allowed by the Navy Department to repair to the office for reducing their hydrography; which, from its nature, cannot be so well done in any other way as under the immediate inspection of those who have executed it. During a brief period in the spring or summer, and during the autumn, the seasons of active employment overlap; but the interval is not considerable between the closing of operations in one set of sections and the beginning of those in the others. The whole number of navy officers on coast survey duty was fifty-two on the 1st of March, 1851; and on the 1st of September, 1851, was sixty-six. There are on duty afloat, now, when the parties are full, fifty-five officers, and on office duty eleven. The names of the officers detailed are given in Appendix No. 3 and No. 3 bis. The Coast Survey provides the vessels for these parties, keeps them in repair, fits them out, and provides for current surveying expenses from the appropriation. When steam is used, the coal, wood, oil, &c., are provided by the coast survey. The engineers attached to the steamers are from the navy, and the names of those now on service in the Coast Survey are given in Appendix No. 4 and No. 4 bis. The

transportation of cificers is paid by the survey, and during the past

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year has fallen heavily upon it: officers being directed to report by letter, and not, as heretofore, in person, to the Secretary of the Treasury, so that their transportation in joining has been paid from the appropriation for the survey, and not from the naval appropriation. Draughtsmen are provided, while the parties are in the office, from the coast survey appropriation, being allowed as clerks to the chiefs of parties only when afloat. I have found it necessary to include additional items for these expenses in the estimates for next year. Nearly half the officers of each party being detached from the survey as the parties take up their office work, that afloat is always resumed with the disadvantage of inexperience; which makes the work less valuable and more costly, and sometimes prevents the execution, by the chiefs of parties, of as much as they would desire to accomplish. While the obligations of the survey to the officers of the army and navy serving on it are freely and fully acknowledged, it should not be forgotten that, on the other hand, the work serves as a school of practice for them, and thus gives while it receives. The statistics from the records of the Coast Survey office, furnished in the table Appendix No. 5, show the large amount of work done, and of results ... up to the beginning of 1851. The number of original topographical maps is 301, consisting of 483 sheets; of hydrographical maps 735; and of reduced maps and charts 220. The extent of shore line already surveyed is 11,873 miles. A list of the discoveries and developments made on different parts of the coast is also printed in the Appendix, (No. 6.) As a summary of these was given in my report of last year, I do not propose at this time to repeat it, but merely to call attention to the new results obtained this year, viz; those upon the Nantucket shoals, as shown in the sketch accompanying this report; the minute survey of the rocks in Hellgate and in Buttermilk channel, to mark the changes effected by blasting; the thorough examination of the Chincoteague shoals, near entrance to the Chesapeake; the examination of the Frying Pan shoals near Cape Fear, and of Cape Fear entrance; the survey of t harbor of refuge of North Edisto, South Carolina; of Tybee bar and Savannah harbor; of Key West; of the mouths of the Mississippi; and of Humboldt and Trinidad bays, in California. A. The importance of circulating the sketch of Nantucket shoals among our navigators is very great; as, notwithstanding that frequent publications have been made in regard to them, vessels still incautiously approach too near them. Within the past summer one of our national vessels touched upon Davis's New South shoal, the position of which was published in 1846. The extent of the Chincoteague shoals and of the Frying Pan shoal appear to have been very erroneously laid down hitherto, and are now given, as well as the depth of water upon them,

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