examination is apparent, however, from the many lights on the coast and lakes, and the fact that, on some parts of the coast, the lights are now so numerous that it is impossible to distinguish one from another, and they are hence becoming a nuisance.

The exceptions referred to above are, the three additional appropriations recommended by this office, viz: For the light-house on Horse Shoe reef, Niagara river, $25,000; for a light-house on Bodkin shoal, mouth of the Patapsco, (seven-foot knoll,) $17,000 dollars; for a light-house at the upper jettee, Cape Fear river, including a bridge from the shore to the light-house, $13,000. These are works which it has been determined to prosecute, and need not, therefore, be examined. I have the honor to be, sir, respectfully, your obedient servant, S. PLEASONTON.

WILLIAM L. HODGE, Esq.,

Acting Secretary of the Treasury.

APPENDIX No. 15.

APPENDIX No. 16

Letter of the Superintendent to the chiefs of hydrographic parties in the coast survey, enclosing a communication from the secretary of the Light-house Board, asking for suggestions for the improvements and extension of the present light-house establishment, and extracts from their replies.

COAST SURVEY STATION,

Near Portland, Maine, July 30, 1851.

SIR: I have to call your attention to the enclosed communication from the secretary of the Light-house Board, and to ask such information in relation to the subjects embraced in it as your especial experience on the coast survey, or general experience as a seaman, may enable you to furnish. I would suggest that specific answers be framed, when the subjects come within the range of your experience, to the questions addressed, adding such remarks as the introductory part of the letter seems to contemplate. Please address your reply, as a report, to me at Portland, Maine.

Yours respectfully,

A. D. BACHE, Superintendent, &c.

TO CHIEFS OF HYDROGRAPHIC PARTIES in Coast Survey.

Extracts from letter of Lieutenant Commanding C. H. McBlair, United States navy, assistant in coast survey, in reply to above letter of the Superintendent, in relation to lights, beacons, and buoys needed on the coast of Massachusetts-Section I.

U.S. SURVEYING STEAMER BIBB,

New Bedford, August 28, 1851.

SIR: I have received your letter of the 30th ultimo, directing my attention to the enclosed communication from the Secretary of the Light-house Board, on subjects belonging to improvements in the navigation of our coast.

"Additional lights, buoys, beacons, &c., that may be required to render navigation safe and easy."

The following objects seem to me worthy of the consideration of the Light-house Board:

a. The expediency of substituting a light-house on the ledge called "Sow and Pigs," standing near the entrance into Buzzard's bay, for the present light-boat moored in that vicinity, and the light-house on the western side of Cuttyhunk island. The ledge in question is said to be capable of affording a solid foundation of rock for such a structure, and a light of the highest range and power at this point would be invaluable to vessels passing into Buzzard's bay, the Vineyard sound, or bound westward into Long Island sound.

c. Placing a floating beacon, with a fog-bell attached, on Davis' new South shoal.

This shoal lies near the most frequented parts of the ocean, and has occasioned some very disastrous wrecks. It has as little as eight feet water upon it—is swept by very strong tides, and, during the summer

months, almost constantly hidden by fogs. It was designed at one time to erect a beacon upon it, but the great difficulties of the undertaking, arising from the character of the climate and the distance of the nearest port, seem to be regarded as insuperable. It is, however, indispensable to the safety of passing vessels that it should be marked in as distinct a manner as circumstances will admit.

d. A buoy-boat (hereafter to be described) on the Great Rip, one of the most extensive of the Nantucket shoals. A suitable place for this mark would be in the slue or passage near the south end. I would here indicate the shoal itself, the passage in which it was moored, and that on either side of the Rip.

e. A buoy-boat on the small shoal lying to the eastward of the northern end of the Bass Rip, (Nantucket shoals,) to mark the shoal itself and indicate the passage generally between the Bass and Great Rip.

f. A spar-buoy (hereafter to be described) on the sand-spit projecting from Fox's point, (Nashawena island,) at the southern entrance into Quick's Hole. This channel, connecting the Vineyard sound with Buzzard's bay, is constantly used, and the want of a mark showing the spit has occasioned frequent wrecks.

g. A light-boat near Brenton's reef, at the mouth of Newport harbor, already recommended in a special report to you.

h. Three small harbor-lights, to facilitate the entrance into Holmes' Hole harbor, already particularly described in my report to you of the 16th ultimo.

i. Certain spindles, buoys, and beacons, marking the approaches near Dorchester and Boston, already enumerated and described in my reports to you, dated March 1st.

j. A wooden beacon, painted black, on Long island, (Boston harbor,) placed so as to range with the northeast end of Spectacle island, for the safe navigation of the main ship channel. For particulars respecting this mark, I beg to refer you to Lieutenant Charles H. Davis' report to you on the subject, of December 24, 1847.

k. A similar beacon on the southeast part of Long island, (Boston harbor,) to range with "Nix's Mate," in order to facilitate the passage through the Broad Sound south channel. In the Coast Survey sailing directions, the range that has been given to answer the same end, is "Nix's Mate on Blue Hill;" but owing to the distance of the latter object, this guide is only available in clear weather. The substituton of the beacon on Long island for Blue Hill, is recommended at the instance of Lieutenant Davis.

7. A buoy-boat on the southwest end of Billingsgate shoal, (Massachusetts bay,) and two spar-buoys on the southern edge of the shoal, planted at regular intervals between the boat and Billingsgate island. Three guides are necessary in the approach to the anchorage under Billingsgate shoal.

m. A spar-buoy on or near a small rock lying to the southward of Wellfleet harbor, and called, on the hydrographical sheet, "Bibb Rock."

Respectfully,

C. H. McBLAIR,

Lieutenant Commanding, and Assistant Coast Survey.