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bay; to make the computations and reductions required for

the work of the section,—will reqnire... .......... SECTIONS X and XI. Western coast, California and Oregon.

See estimate provided for, as last year, by special appropriation.

$21,000

Total, exclusive of Florida reefs and keys, and of the west

ern coast.........................................

186,000

SECTION VI. To continue the survey of the Florida coast,

reef, and keys. Field work.—Tocomplete the triangulation of the Walker keys; to continue that of the reef from Key Rodriguez southward and westward to Key Vacas ; to continue the secondary triangulation of the western coast of Florida from Crystal river southward; to complete the topography of the keys to the limits of the triangulation; to continue the hydrography of the outer coast and reef, from Ajax reef southward. Office work.—To make the necessary computations and reductions; to complete the drawing of Boca Grande passage, and Bahia Honda, and the engraving of the chart of Kcy West harbor and the approaches; and sketches

of the Boca Grande passage and Bahia Hondawill require $30,000 Sections X and XI. * To continue the survey of the west

ern coast, Oregon and California. Field work.—To determine the geographical positions, absolute and relative, of the most important capes and headlands in California and Oregon; to complete the triangulation of San Francisco and San Pablo bays, &c., and of Santa Barbara sound; to complete those of the several harbors already examined; to continue that of the Columbia river, and of Puget's sound; to complete the topography for the harbor charts already commenced, and for the sites of light-houses; to complete the hydrography of the Columbia river; to continue that of San Francisco bay, of Monterey, Santa Barbara, &c.; to complete the general examination of the harbors of the coast and to revise the general reconnaissance of the coast. Office work.- To make the computations and reductions; to complete the drawings and engravings for the sites of lighthouses, and of the examinations of harbors; to continue those of San Francisco bay, Monterey, and the revised reconnaissance; to provide for the drawing and engraving of sketches received; for the engraving of the revised general coast reconnaissance; of the Columbia river survey;

of Santa Barbara sound, &c.,—will require............. 150,000 The appropriation for the western coast will include the ne

cessary repairs and expenses of a steam-vessel, and will

add one party to those operating in that quarter. The appropriation for the coast of the Atlantic and Gulf of Mexico in 1850–51, was..........

186,000 For the Florida reefs, keys, and coast........... ........ 30,000 For the western coast, including the cost of a steam-vessel.. 190,000 For the next year—the present fiscal year-the appropriations were severally $180,000, $30,000, and $100,000. I am satisfied, from experience, that the sums now asked are as small as, with the most economical administration of the survey, the work marked out can be executed for; requiring a close and constant care to make them give these results. The plan of operation is in a degree deranged, and the relative parts make a progress not adapted to each other, when the amounts are lessened; besides which, a portion of the work is necessarily cut off, and the survey makes slow progress. I am of opinion that true economy in such a work is to be found by enlarging the operations, thus increasing the division of labor. The work being of a temporary character, the enlargement of its expenditures is more than made up to the treasury by its less duration.

I proceed, next, to give a more particular account of the operations on the several sections of the coast, derived from the reports of the assistants and others employed; prefacing the more detailed statements with remarks on the progress of the section, and on the more interesting general results. The incidental notices of the office-work which thus occur in connexion with the sections, are followed by a complete detail of the progress in its various departments.

A table of occupation of the field and hydrographic parties is given in the Appendix, (No. 1,) showing their distribution during the different seasons appropriate to surveying different parts of the coast.

The light-house work executed in the different sections is stated in the general table, (Appendix, No. 15,) and more in detail under the head of each geographical section of the coast.

In the Appendix to this report, Nos. 13 to 14 bis, inclusive, will be found the instructions of the Treasury Department, and the general correspondence on the subject of light-houses, &c.; special reports being elsewhere given in the Appendix, in connexion with the section to which they refer. The Appendix No. 16 contains a circular to the chiefs of hydrographic parties, referring to a communication from the secretary of the Light-house Board, asking suggestions for the improvement and extension of the present light-house establishment, and extracts from the replies.

SECTION 1.-FROM PASSAMAQUODDY BAY TO POINT JUDITH, INCLUDING

THE COAST OF MAINE, NEW HAMPSHIRE, MASSACHUSETTS, AND RHODE ISLAND.-(Sketch A.)

The new appropriation having been available from the very beginning of the fiscal year, the work in this section has made very good progress. Two triangulation, three topographical, and two hydrographic parties, were at work during nearly the whole of the season; one of the triangulation parties making also the astronomical and magnetic observations connected with the primary work; two of the topographical parties using each two plane tables; and one of the hydrographic parties having, for the greater part of the time, three vessels one of them a steam-vessel. The primary triangulation was extended to Cape Small Point, at the mouth of the Kennebec, and the reconnaissance for it beyond the Penobscot. The secondary triangulation was completed to Portland. The topography of Cape Cod, Cape Ann, and Newburyport harbor, in Massachusetts, was nearly completed. The hydrography of Nantucket shoals was continued; that of Salem, Chatham, Portsmouth, and Newburyport harbors completed; off-shore work off Block island and Gay Head was executed; and tides and currents were observed near the Elizabeth islands, in the Vineyard sound and Buzzard's bay, at Holmes' Hole, Salem, Newburyport, and Portsmouth. The permanent tidal station at Charlestown, Massachusetts, has been kept up, and observations for several lunations have been made in Salem, Portsmouth, and Newburyport harbors. The office-work has made corresponding progress. Accompanying this report (sketch A, No. 3) is a current chart, showing the nature and results of observations of previous years in the harbor of Boston. The preliminary chart of Richmond's Island harbor, issued to meet the wants of the Committee on Commerce, has given place to a more complete map. During the great gale of April last, the violence of which was especially felt on the coast of Massachusetts, an opening was made through Chatham beach, (see sketch A,) giving a more direct and deeper entrance to the harbor of Chatham than had previously, at least of late years, existed. This attracted much attention, and hopes were entertained that a harbor of refuge might thus be obtained at a point where one was much needed. I incorporated in the instructions of the season directions to examine Chatham harbor, and if the bar and entrance were found in a moderately permanent condition, to make a complete survey of it. The topographical party of Assistant J. B. Glück was instructed to complete, without delay, the shore line; and Lieutenant Commanding Woodhull to take some convenient opportunity, towards the close of his operations in the Vineyard sound, to make the desired examination. This was promptly executed. The greatest depth which he found could be carried over the bars, at high water, was eleven feet; the rise and fall of the tide being about four and a half feet. There is deep water—in one spot twenty-two feet at low water—near the village of Chatham. The changes from week to week in the outer bar, he was satisfied, were such that a chart could not be made which would be of service to navigation. He accordingly recommended the postponement of the survey until a more permanent condition was ... making, meanwhile, quite a careful examination. which has been plotted, and the chart representing which has been placed on file in the office, where it may be consulted by, or copied for, those who are especially interested in the matter. The occupation of some twelve more stations will complete the pri mary triangulation to the northeastern boundary. The reasons which render it more expedient to employ a party only during part of the season for this purpose, have been frequently stated. The primary triangulation is still in advance of the secondary, though, in consequence of the desirableness of prompt surveys of some of the harbors in the more eastern part of the section, that operation has been pushed well forward. The difficult and comparatively expensive hydrography of the Nan

tucket shoals, has delayed the hydrography beyond my calculations. The transfer of one of the southern hydrographic parties to this section formed part of my plan for the past season, which was interrupted by causes beyond my control, and which it is not necessary here to state. The plan is only deferred, not given up. The examination for a base of verification will be made next season, or in the following one; and, should a suitable one be found, the triangulation will be directed in reference to a junction with it.

The tides, and currents resulting from them, in the passages between the Elizabeth islands are altogether peculiar, and require close investigation. On one side of the islands the rise and fall belongs to Buzzard's - bay; and on the other side to the Vineyard sound. The Buzzard's bay tide is propagated through the entrance between Cuttyhunk and Saghkonnet Point. (See sketch A.) The two chief passages used by vessels between the Vineyard sound and Buzzard's bay are Wood's Hole and Quicks' Hole. The plan which I sketched for determining the facts in regard to the tides was the establishment of three tide-gauges, to be observed during the same period on the north side of the Elizabeth islands at Wood's Hole, Kettle cove, and Quicks' Hole; and on the south side at Wood's Hole, Tarpaulin cove, and Quicks' Hole. These observations would give the corresponding phenomena and their progress between the two passages, and, being completed satisfactorily, the gauges from Kettle and Tarpaulin coves were to be removed to points nearly midway, or, better, at or near the point of ineeting of the tides from the bay and sound, between the two gauges in Wood's and the - two in Quicks' Hole, so as to determine the relation of the movement in these passages. This plan has been satisfactorily carried out during the present season, except that three days of simultaneous hourly observations, which I considered essential to its completeness, could not be made on account of the boisterous character of the weather.

During the season I had repeated conferences with the chiefs of parties in this section when the diversified operations required it, but made no special inspection. The inspection of a portion of the operations was made by Major I. I. Stevens, of the corps of engineers, assistant in charge of the office.

In 1849, a special expedition for the determination of the difference of longitude between the coast survey stations and European observatories was organized and reported upon. During the following year the reduction of the observations was made, so as to draw upon the experience of that operation for improvement in a subsequent one. During the past season the second trial has been made, the general results of which will be stated in their place from the report of Professor W. C. Bond, director of the Cambridge observatory, by whom, in concert with Mr. Hartnup, director of the Liverpool observatory, the work has been executed.

Arrangements have also been made, through Professor Bond, for connecting the coast survey of the United States with the surveys making by the British government in Nova Scotia. The occasion will be taken to obtain the longitude, by telegraph, of Bangor, in Maine, an important point in every respect, while facilitating the connexion of Cambridge and Halifax. The thanks of the Survey are due to H. O. Alden, esq.,

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the president of the Maine Telegraph Company, for assistance rendered in these operations. (See Appendix, No. 18.)

The appropriations for light-houses, beacons, buoys, &c., embraced in the bill approved March 3, 1851, for localities within this section, were the following:

"Maine.-1. For buoys on White's and Thom's ledges, and on Pond Island reef, at the mouth of the Kennebec river, three hundred dollars.

“2. For a light-house on Pond island, at the entrance of Narraguagus bay, four thousand dollars.

"Massachusetts.—3. For a light-boat on the Shovelful shoals, off Chatham, twelve thousand five hundred dollars.

“4. For eleven buoys in the channel to Commercial point and Neponset river, in Dorchester, one thousand dollars.

“5. For a light-house at the head of Holmes' Hole harbor, three thousand five hundred dollars.

“6. For a beacon on Fawn bar, near Deer island, Boston harbor, two thousand five hundred dollars.

“7. For two iron spindles on the northeast ledge of the Graves, and on Harding's ledge, Boston harbor, two thousand dollars.

Rhode Island.-8. For a light-boat off Brenton's reef, fifteen thousand dollars."

Examinations of all these were required, under the law, by the Fifth Auditor, and were made, according to the instructions from the Treasury Department, under my direction. My reports will be found in the Appendix, (Nos. 19, 20, 21, and 22,) accompanied by those of the assistants of the survey to whom the examinations were referred, (Lieutenants Commanding Charles H. McBlair and Maxwell Woodhuli, United States navy,) which contain all the details necessary to an understanding of the subject. In every case a thorough examination of the localities was made, wherever the coast survey extended, by the aid of its charts, and the reports state fully the requirements of navigation in reference to the objects embraced in the bill.

The buoys at the mouth of the Kennebec (No. 1) were recommended to be immediately placed, (July 28.) The light-house on Pond island, Narraguagus bay, (No. 2,) was also recommended to be erected, to contain a revolving light. A light-boat on the southeast extremity of Shovelful shoals, off Chatham, (No. 3;) a beacon on Fawn bar, near Deer island, (No. 6;) and two iron spindles on the Graves and Harding's ledges, Boston harbor, (No. 7,) and the light-boat off Brenton's reef, (No. 8) ---were recommended to be placed. The buoys in the Neponset river (No. 4) had already been reported upon favorably from the Office of the Coast Survey. Instead of the light-house at the head of Holmes' Hole, three small beacon-lights, (technically called “buglights,") for ranges, were recommended, and their positions indicated on a chart. It was supposed that the three beacon-lights could be put up for the amount of the appropriation for a single light-house.

A fog-whistle for the light-house on Petit Menan island, instead of the present fog-bell, and a buoy on Thomas' reef, near Thom's reef, at the entrance of the Kennebec-objects for which an appropriation had been made-were reported as desirable. · The reports of the examining officers not only show that there are

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