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officers to say, that though they had just returned from arduous service in the Gulf of Mexico, there was no abatement of zeal and industry in the prosecution of the new duty assigned to them, as, indeed, the statistics of the work just given most amply prove.

Light-houscs, 8C.-In accordance with the instructions of the Treasury Department, pursuant to an act of Congress, Lieutenant Commanding J. J. Almy, United States navy, assistant in the coast survey, was directed to make an examination of the necessity for a light-house at Fishing battery, otherwise called Donaho's battery, in Chesapeake bay, near Havre de Grace, Maryland. His report, and my recommendation or the erection of a light-house, will be found in Appendix No. 27. SECTION IV.–FROM CAPE HENRY TO CAPE FEAR, INCLUDING THE COAST

OF THE STATE OF NORTH CAROLINA.—(Sketch D.)

Two parties for triangulation and one for hydrography have been employed, during the whole of the past season, in this section; and during a part of it, in addition, a reconnaissance party and two hydrographic parties. The secondary triangulation of the season covers the gicaier part of Currituck sound; and the tertiary extends from Hatteras light to a point south of Ocracoke inlet. A general reconnaissance of Pamplico sound has prepared the way for the main triangulation. With this was united an examination of Core sound. The hydrography of Albemarle and Croatan sounds, remaining from the previous year's work, and that of Roanoke sound, have been completed; as also, in part, that of Currituck sound. Oregon inlet, which opened in 1846, was re-examined, to ascertain its progress.

The reports of the officers engaged in these surveys contain matter locally and generally interesting, which will be mentioned or quoted in due connexion. Reports upon Cape Fear river and Beaufort harbor, in reference to location of lights and buoys, will also be presented in their place.

To obtain the difference of longitude of a point in this section from Washington, the telegraphic connexion with Portsmouth, Virginia, was used, and chronometers transported from thence to Forbes' Point, near Elizabeth City, in North Carolina. Portsmouth is an important locality in the geodetic operations of the survey, as the southern extremity of the arc of the meridian which passes northward over the Chesapeake to the Delaware, and the measurement of which has now nearly been completed in the regular progress of the survey.

The drawing of one sheet of the general chart of Albemarle sound has made considerable progress, and that of Beaufort harbor is complete, and ready for engraving. Sketches of Hatteras shoals, Hatteras inlet, and Beaufort harbor, accompany this report, and provision has been made for engraving those of the entrance to Cape Fear, and the Fryingpan shoals off Cape Fear, as soon as sent in to the office.

Ít appears from the examination of Pamplico sound that it contains a number of excellent harbors, often needed for refuge, yet scarcely used from want of acquaintance with their intricacies.

The channel of Core sound, sounded in accordance with a special request of the legislature of North Carolina, was found to have undergone no substantial change.

Oregon inlet, which has been watched with interest as holding out hopes of a new entrance important to the navigation of Albemarle and Pamplico sounds, does not, in its present state, afford much encouragement to such an idea.

The harbor of Beaufort appears to be less liable to deterioration than other points on this part of the coast, and may be pronounced equal, in its security and natural facilities, to any port of our eastern coast south of the Chesapeake. It allows 17 feet to be carried in at low water.

A survey has been made of the Fryingpan shoals, (of which there appears to have been heretofore but little correct knowledge,) and of the approaches to the bars of Cape Fear river. The description of the shoals and channels, and the recommendations on the subject of lights and buoys, resulting from this examination, will be found at length under their proper head. A survey of Cape Fear river, interior to this, is also in progress.

An examination of Hatteras inlet has been made, in reference to which it is reported that “No important perceptible changes had taken place on the bar or in the channel, except near the anchorage; the sand and spits had become beiter defined, and the area of the anchoring ground had increased, with a greater depth of water as far as the bulkhead. No greater depth of water over the outer bar and on the bulkhead was found.”

The deep-sea soundings and soundings for temperatures in the Gulf Stream have been prosecuted during the season in this section.

Astronomical, telegraphic, and chronometer observations. These were under the charge of assistant Sears C. Walker. The scheme as organized was to determine the longitude of Portsmouth, Virginia, by the aid of telegraphic connexion with the Seaton station at Washington city, and from the former to deduce that of Forbes' Point, a station about forty-five miles distant, by the daily transportation of chronometers. In preparation, the chronometers had, for six weeks, been daily compared and rated by transit observations at Washington. Assistant Pourtales and Mr. J. Ř. Offey conducted the chronometric expedition, comparing night and morning, by coincidence of beats, the chronometers daily exchanged between Portsmouth and Forbes' Point. The former made the transit observations at Forbes' Point, and Mr. J. C. Langton those at the Washington station. Assistant Walker superintended the exchange of clock signals on the Seaton chronograph. The observer at Portsmouth tapped on the break-circuit key every five seconds for one minute, for each chronometer, and the hour and minute thus tapped were noted, the signal being registered by the instruments at Portsmouth, Petersburg, and Washington.

During seven days the success of the ob ervations and exchange of signals had been ainply favorable, when their progress was temporarily arrested by prolonged failure of the telegraph line after a storm. The operation was continued as far as the means at our disposal and the other exigencies of the season's service permitted. It is not considered, however, as completed.

Reconnaissance. (sketch D.)—The party and vessel employed in the tertiary triangulation were, for about six weeks, withdrawn from that duty and assigned to the use of Major H. Prince, United States army, assistant in the coast survey, who made the reconnaissance and accompanying sketch of the sound usually known as “Pamlico.” Major Prince refers to good maps, to the usage of the neighborhood, and to the oldest authorities, as condemning this orthography, and gives Pan plico as the name which appears to have ihe weight of authori.y in its favor.

Describing ihis sound, Major Prince says: “!is breadth from Roanoke island 10 Long shoal increases from nine to eigh.een miles, and in the rest of its lengih it has a general breadth of from iwenty to thirty miles. The gene:al depih of the channel is fiom three to four fathoms." He notes the fact mentioned by Williamson, a historian of the State, forty years ago, that lands then planted wiih corn were covered with water at the beginning of the eighteenth century; and observes that it the same causes, whatever they may be, continue to operate, there will be large tracts of the richest possible soil reclaimed for cultivation along this coast. A growth of small live-oak about Ocracoke, it is remarked, vigilantly preserved, protects the soil from the action of the winds.

The exposure of this sound is such that navigation is ofien dangerous, and vessels have to put back some distance for refuge. Yet the desired harbors are reported to be numerous and converient, and, to be useful, require only to be made koown.

With reference io Core sound, the supposed changes of which had caused the legislature of the State to request its examination, Major Prince reports that he has carefully compared it with the chart of a survey made by Captain T. J. Lee, United Siates topographical engineers, in 1837. The result is thus stated: “A few small differences of soundings, (we having no tidal observations,) and some small differences of the course (allowance bein"; made for some dredging, of which I have no account, on Piney Po'nt shoal)-in the main, leave the present channel and that of the chali, as it was fouiieen years ago, alike.”

The sketch by Major Prince, above referred to, shows the scheme for the main triangulation obtained by his reconnaissance.

Secondary triangulaiion, (sketch D.)- In the season of eight months, (November to July.) assisiant J. J. S. Hassler extended this branch of the work along Currituck sound, from Thoroughlare island to the Virginia line. The area embraced was 73 square miles; 12 stations were occupied, and 11 determined; and 871 angles measured by 5,226 observations. The party had the use of the Coast Survey schooner Vanderbilt.

A secondary triangulation, and the requisite topography connected with it, of the entrance to Cape Fear river, was executed by assistant Charles P. Bolles, aided by Nİr. J. W. Gregorie, and the resulis immediately computed and furnished to the hydrographic pariy working at the same point. A prelimin: ry b ve, rainer exceeding three miles in length, was measureu wich a chain upon the beach. (See sketch D, No. 6.) From its extrem 'lies nearly every important point in the harbor can be seen, and “tje l'angles are so disposed as to give double determinations of nearly every point of the second order, and of every point of the third order.” The work covers an area of 33 square miles; 8 stations were occupied, and 97 angles, on 17 objects, measured with a six-inch repeating theodolite by Gambey, (C. S. No. 35.) The plane

the gecondary triguing anche sound freuen

ions.

condane entranded by sted

with it, of ihny triangulaiiuse of the C

table survey connected with it furnished 52 miles of shore line, and included the town of Smithville.

The party of assistant Bolles had already been engaged in section V, and were transferred to this section in June, remaining until the close of September.

Tertiary triangulation, (sketch D.)- A party, under sub-assistant A. S. Wadsworth, aided by Mr. C. T. Jardella, with the Coast Survey schooner Bancroft, was engaged in this triangulation from early in December until late in March. It was then withdrawn for use in reconnaissance, and, after some weeks, again occupied, for a short time, in marking with granite posts the most important stations of the preceding year.

The triangulation extended from Cape Hatteras to Ocracoke inlet, 35 miles along the coast, and covered an area of 977 square miles; 19 slations were occupied and 77 angles measured, by 450 observations, with a six-inch repeating theodolite of Gambey, (C. S. No. 29.)

Topography, (sketch D.)- Assistant Henry L. Whiting spent a month, with a party and vessel, in a topographical survey of the harbor of Beaufort. His work will, in connexion with other surveys, furnish a complete harbor chart. For the gratification of those specially interested, I annex descriptive extracts from his report. (See Appendix, No. 28.)

The amount of work accomplished may be thus stated: Area, in square miles, 22; extent of shore line, 39 miles; outline of shoals, &c., 15; length of creeks, 18; and of roads, 16 miles.

Assistant Whiting points out the causes which, in his opinion, tend to preserve the interior of this harbor from change, and the same general depth of water on the bar. These will be found in the Appendix, as above referred to; though I am not prepared to endorse the views expressed in reference to currents caused by Cape Lookout.

Hydrography.(See the several sketches.)—Lieutenant Commanding Richard Wainwright, United States navy, assistant in the coast survey, with the surveying schooner John Y. Mason, was engaged in this section during the latter part of 1850, and from April to June, 1851. The hydrography of Roanoke and Croatan sounds, with the small portion of Albemarle sound remaining from last year, has been completed, and that of Currituck sound carried north, as far as the points marked Woodis and Willet's on the sketch. Thirty-three thousand eight hundred and seventeen soundings were made; 1,066 angles taken; and 496 miles of soundings run; nearly all done in boats.

Lieutenant Wainwright also visited Oregon inlet. He found the breakers extending entirely across the bar. The bulkhead towards Albemarle sound remains unchanged, having about three feet of water at mean tide.

Lieutenant Commanding J. N. Maffitt, United States navy, assistant in the coast survey, with the hydrographic party under his command, (which has been for the most part employed in Section V,) visited this section in December last to complete the hydrography of Beaufort, North Carolina; and has furnished a chart of the bar and harbor. (Sketch D, No. 5.)

The statistics of this supplementary work in Beaufort harbor are as

vations same party drographical perth Caro

follows: 53 miles sounded over by 1,289 soundings; 88 angles measured; 36 specimens of the bottom obtained; and three sets of observations were made upon currents.

The same party returned to this section and undertook, in October of this year, the hydrographical reconnaissance of the entrance to the Cape Fear and of New river, North Carolina. The lateness of the season prevents their results from being received in time to be embodied in this report.

Tidal observations have been made at Smithville (Fort Johnson wharf) day and night, since July 1, and five current stations have been occupied.

Lieutenant T. A. Jenkins, United States navy, assistant in the coast survey, commanded another hydrographic party, in the Coast Survey steamer Corwin. His operations have been directed—1st, to the reexamination of Hatteras inlet, to place it on the sheet of Hatteras shoals by the aid of the extended triangulation, and to ascertain whether any important changes had taken place; the results have been already indicated, (see sketch D, No. 3:) 2d, to the deep-sea soundings and soundings for temperatures in the Gulf Stream, (sketch D, No. 4:) 3d, to the survey of Fryingpan shoals and the approaches to the main and New Inlet bars at the mouth of the Cape Fear river, (sketch D, No. 8.)

The statistics of his season's work are as follows: Area of hydrographic sheet.

250 sq. miles. Number of soundings taken......

...21,990 Number of angles measured......

4,300 Number of lines of soundings run....... Number of miles of soundings......

540 Number of specimens of bottom preserved..... 46 Number of lines of deep-sea soundings run..... Number of miles of deep-sea soundings run.......... Number of positions for deep-sea soundings and temperatures in the Gulf Streain....

4 The report of Lieutenant Commanding Jenkins on the Fryingpan shoals, and his suggestions in reference to the facilities required for navigation, are of such interest that I extract them in full:

“The Fryingpan shoals-extending from the southeast point of Cape Fear, in almost a SSE. direction from Bald Head light-house to the distance of twenty nautical miles, to ten fathoms water, with an average width of four miles—and the approaches to the main and New Inlet bars at the mouth of the Cape Fear river, have been carefully surveyed, and the sheet is now nearly ready for reduction to the publication scale.

“The pilots and others in the vicinity had little correct knowledge of these dangerous shoals, and the great distance to which they extend from the shore rendered the work one of more than ordinary difficulty.

“The shoalest spot outside of Bird shoal, (near the point of the cape,) has 7, 8, and 9 feet water on it at low water, distant 13 nautical miles from Bald Head light-house, and bearing NNW, from it by compass.

“There is another shoal spot with ten feet water at low tide, 141

313

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