REPORT ON THE COAST SURVEY

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CHARTS PUBLISHED.— The charts which have been described, in their general character, in the first part of this report, exhibit such an exact and clearly intelligible delineation of the coast-line in its contour and topography, and of the adjacent waters off-shore, and in bays and inlets, and, to a certain extent, even in rivers, as to enable the mariner to choose his course with confidence, avoiding hidden dangers, and following the secure channels as easily as if the sea-bottom itself were exposed to his view. Or, rather, they are a safer guide than the sight of the bottom could be; since they enable him at a glance to take in a wide area on the chart, while a direct inspection could extend, even under the most favorable circumstances, only to a limited space in the immediate vicinity of his vessel. The number of such delineations, or charts, which the American Coast Survey has produced, is already very great: various in character, according to the immediate objects which they are designed to subserve. Of the finished charts, there have been published forty-seven sheets of charts of harbors, anchorages, and the like, to various scales, from 1/5000 to 1/8000; eight sheets of “in-shore” or coast-charts, to scale of 1/80000; and one sheet of “off-shore” or general coast-chart, to scale of 1/400000. Of the preliminary sea-coast and harbor charts, there have been published upwards of eighty sheets, to various scales from 1/10000 to 1/400000: and of hydrographic sketches, upwards of one hundred and twenty.

As regards the finished maps, it may be said that, in point of execution, they do honor to the government under whose authority they have been put forth. That they are characterized by the greatest precision, may of course be said, since this is the first and essential condition which gives to any map its value: but considered, also, as specimens of art, they are unsurpassed in any particular, whether in the drawing, engraving, or printing, by any works of their class ever produced by public or private enterprise, at home or abroad. There results from this the double advantage, that while their elaborate execution carried with it a certificate of their refinement and accuracy, and gives to the navigator who consults them assurance of their truth, it at the same time reflects credit upon the country, and presents a model for imitation which cannot fail to improve the standard of artistic execution in every work, whether of a scientific or of a purely aesthetic character, produced among our people.

Below is given a list of the finished charts already published, arranged in geographical order, from Maine to Washington Territory; also, a list, arranged in like manner, of preliminary charts and hydrographic sketches published, omitting such of these latter as represent reconnaissances and preliminary surveys afterwards superseded by more detailed surveys.

DISCOVERIES AND DEVELOPMENTS OF THE COAST SURVEY.– Were this Committee to attempt to enumerate or to enter into a detailed specification of all the important contributions to nautical knowledge which the Survey has collected, or to point out all the seriously dangerous errors which it has succeeded in correcting, this branch of their subject would overshadow all the rest, and their report would degenerate into a mere catalogue of hydrographic discovery. Yet, in order that the reader may have the opportunity of informing himself, in some measure, in regard to matters which cannot conveniently be fully presented in this place, we shall add a list of the more important discoveries and developments, and if, in connection with this, we compare the ancient charts with those which have been, in later years, wrought out by the American Coast Survey, we may form some faint idea of its inestimable benefits to navigation. Let, for instance, the charts of the port of New York be examined. By far the most serviceable avenue to this most important of our harbors, the channel (Gedney’s) made use of now by vessels of the largest class, was entirely unknown until it was developed in the systematic hydrography of the bay. Had the true depth of this channel been known in 1778, (then probably existing, as seen by comparing old and new charts,) the French fleet under Count d’Estaing might have passed into the bay, and taken the assembled British vessels. The gradual increase of Sandy Hook to the northward, narrowing the main ship-channel entrance, has been well established by the successive observations of the survey; its cause has been investigated, and the result gives encouragement in reference to the power to control this growth of the Hook, should it become necessary. Take, again, the approach to Philadelphia: until the Coast Survey corrected the error, the two light-houses which define the entrance to the Delaware were variously represented on the charts as from four and a half to seven miles more distant from each other than they are in fact. The great regulating landmark of our pilots, at Bombay Hook, was five miles out of place. The deepest and most sheltered channel in the widest part of the bay, was supposed to be almost a shoal. Take, again, the island of Nantucket, fringed round with a labyrinth of shoals, which seemed to defy all attempts at comprehension:– see it now all pictured out upon these beautiful charts in every minutest detail, like a great citadel with its outworks systematically disposed all around it. Look at the numerous isolate rocks, ledges, reefs, and shoals, on all parts of our far-extending coast-line, located with the utmost degree of precision.

Some of these individual facts– many or most of them, probably– have already been the means of saving many ships from wreck and total loss. There is no extravagance in this presumption, at least if we strike an average, that a single such service may fairly be ascribable, within the past year, to everyone of these additions, to the amount of knowledge previously existing in regard to the hidden dangers or the treacherous currents of the ocean. Let this estimate, for a moment, be adopted; and let the value of ships and their cargoes, small and great, richly and poorly laden, be put at so low an average as twenty thousand dollars; it will appear that we may fairly credit to the services of the Coast Survey an annual saving to the country of nearly three millions of dollars. If in this conclusion there is error, there can be little doubt that it is because the amount is put too low.

The recorded disasters to our marine commerce in 1855, reached still a total, in spite of all the increased security which the charts as far as completed have given to navigation, of almost twelve millions of dollars.

In view, therefore, of all these considerations, the Committee cannot but conclude, that, in so far as the direct objects are concerned for which the survey was instituted, the wisdom of the policy in which it originated is abundantly vindicated, and the largest expectations of benefit from its execution which its projectors professed to entertain, have been more than realized in the results already achieved.

List of the more remarkable discoveries and developments by the United States Coast Survey to the year 1858, arranged in geographical order.

Casco bay, Maine: determination of the position of a sunken rock, on which the steamer Daniel Webster struck, on October 13, 1856.

Gloucester harbor, Massachusetts: a rock (not on any chart) in the inner harbor, discovered in 1853.

Boston harbor: Broad sound channel thoroughly surveyed, 1848; several rocks in the fair channel way, 1854.

Massachusetts bay: Stellwagen’s bank, an important mark for approaching the entrance, 1854; a dangerous sunken ledge (Davis’ ledge) to the eastward of Minot’s ledge, 1854; development of a reef between Minto’s and Scituate light, 1856; a sunken rock, with only six feet at low water, off Marshfield, 1856; a dangerous rock, near Saquish head, entrance to Plymouth harbor, 1856; three rocks, partly bare at low water, off Manomet point, determined in position, 1856; a very dangerous rock off Indian Hill, and four miles south of Manomet point, with only six feet water, 1856.

Nantucket shoals: Davis’ New South shoals discovered, six miles south of the old Nantucket South shoals, and in the track of all vessels between New York and Europe, or from the eastern to the southern states, or to South America, 1846; two new shoals, 1847; six new shoals, the outermost fourteen and a half miles from land, and with only ten feet water, 1848; McBlair’s shoals, 1849; Davis’ bank, 1848; Fishing Rip, a large shoal, with four and a half fathoms, surveyed in 1852; a ridge connecting Davis’ New South shoal and Davis’ bank, 1853; a small bank or knoll, beyond the limits of the series of shoals, with only five fathoms on it, five miles east of Great Rip; two shoal spots, near the northern extremity of Davis’ bank, with fourteen and eighteen feet water, 1856.

Nantucket sound: contraction of the inlet at the north end of Monomy island, and opening of new entrance to Chatham harbor, 1853; Edwards’ shoal, south of Nantucket light-boat, 1855; two shoal spots, with twelve and thirteen feet water, 1856; survey of Muskeget channel, 1848 and 1850.

Numerous rocks in Martha’s Vineyard sound, Long Island sound, and the various bays and harbors connected therewith.

The tides and tidal currents of Long Island sound, of Hudson river, and of the great bay between Massachusetts, Rhode Island, Connecticut, New York, and New Jersey, 1854 to 1857.

New York bay and harbor: Gedney’s channel into New York bay, having two feet water more than the old channels; changes in New York harbor, between 1845 and 1858; increase of depth in Buttermilk channel, 1848; shoal in main ship channel, 1855.

Sandy Hook: its remarkable increase traced from the surveys of the topographical engineers and others, and by several successive special surveys made between 1844 and 1857.

Delaware bay: Blake’s channel at the entrance, discovered in 1844, open when the eastern channel is closed by ice; Blunt’s channel; changes near the Pea Patch.

Coast of Virginia: true extent and position of the dangerous shoals near Chincoteague inlet, 1852; Metonkin inlet, shoaling from eleven to eight feet in the channel, 1852; two channels into Wachapreague inlet, both with seven feet water at low tide, 1852; Great Machipungo inlet, a fine wide channel with eleven feet water on the bar at low ebb, and fourteen at high tide, with good anchorage inside in from two to eight fathoms, forming the best harbor between Delaware and the Chesapeake, 1852.

Entrance to the Chesapeake: two shoals, one 4 3/4 nautical miles S.E. by E. from Smith’s island light-house, with seventeen feet water upon it; the other E. by S. nearly 7 3/4 miles from the same light, with nineteen and a half feet, 1853; finding of only three feet water upon the “Inner Middle,” the shoal part of the Middle Ground, west of the “North Channel,” at the Chesapeake entrance, 1852.

Chesapeake bay: determination of shoals and bars at mouths of Great and Little Choptank, Rappahannock and Patapsco rivers, 1844 to 1855; New Point shoal, with only sixteen feet water, south-east from New Point Comfort light-house, 1854; advantages of York river as a harbor, 1857.

Gulf-stream: discovery of the cold wall, alternate warm and cold bands, and various other features; discovery of cold water at the bottom of the ocean below the Gulf-stream, along the coast of North and South Carolina, Georgia, and Florida, 1853; submarine range of hills, beyond the Gulf-stream, tracked from Cape Florida to Cape Lookout, 1855.
Various facts relative to the distribution of minute shells on the ocean bottom, of probable use to navigators for recognizing their positions.

Coast of North Carolina: dangerous nine feet shoal off Cape Hatteras, 1850; a new channel, with fourteen feet water, into Hatteras inlet, formed during 1852, which is better and straighter than the old channel; changes at Hatteras and Ocracoke inlets, 1857; general permanence in depth on the bar of Beaufort harbor, with the change of position of the channel, 1854; the well ascertained influence of prevailing winds in the movement of the bars at Cape Fear and New Inlet entrances; the shoaling of Cape Fear river bar thoroughly examined for purposes of improvement, 1852, and the changes in the bars and channels determined, 1855 and 1857; Frying Pan shoals, off Cape Fear, extending twenty nautical miles from Bald Head light-house, surveyed in 1851.

Coast of South Carolina: Maffit’s new channel, Charleston harbor, with the same depth of water as the ship channel, 1850; changes in the channels of Charleston harbor, and in the entrances to North Edisto river and Port Royal harbor, 1852 to 1857.

Florida reefs: a harbor of refuge (Turtle harbor) to the northward and westward of Carysfort light-house, with a depth of water of twenty-six feet at the entrance, 1854; a new passage, with three fathoms water, across the reef, to Legaré harbor, under Triumph reef, (lat 25° 30' N., long. 80° 03' W.) Which, if properly buoyed, will be valuable as a harbor of refuge; a safe rule for crossing the Florida reef near Indian Key, 1854; a new channel into Key West harbor, 1850; Isaac shoal, near Rebecca shoal, not laid down on any chart, 1852.

Mobile bay: in 1832, only seventeen feet at low water could be carried over the entrance bar; in 1841, it had nineteen feet, and in 1847, twenty feet and three quarters, as shown by successive surveys; diminution, almost closing, of the passage between Dauphine and Pelican islands, 1853.

Harbors on the coast of the Gulf of Mexico: determination of bars, shoals, and passes, and of the effect of wind in disturbing the tides.

Pacific coast of the United States: various surveys and charts of small harbors, and a continuous reconnaissance of the entire western coast and islands adjacent, a great part of which was imperfectly known, 1849 to 1857.

Coast of California: development of a bar at the entrance of San Diego bay, 1856; a shoal in San Diego bay, with only twelve and a half feet water, not on any chart, 1852; determination of the position and soundings on Cortez shoal, and of a point of rock thereon, 1853 and 1856; position of a rock off Point San Pedro, on which the steamer “Uncle Sam” struck, 1855; discovery of red sand in soundings, marking the entrance to the Golden gate, 1855.

Columbia river: south channel surveyed and made available to commerce, 1851; changes of channels, their southward tendency, and a new three fathom channel from Cape Disappointment, due west, to open water, 1852; further changes, 1853:
Coast of Washington Territory: shoals and dangerous rocks determined in position, in the Strait of Juan de Fuca, Canal de Haro and Rosario straits, 1853 to 1857.

Additional List for 1858, of some of the more remarkable discoveries and developments.

Coast of Maine: dangerous rocks off Boon island, Cape Neddick, and the mouth of York river, determined in position; development of fishing ledge, Boon island ledge, and Duck island ledge; a detected rock two-thirds of a mile northward and eastward of York ledge.

Coast of New Hampshire: a very dangerous rock, with only six and a half feet water, off the entrance to Portsmouth harbor, about four nautical miles eastward from the Whale’s Back light; a rock, with twelve meet at mean low water, about four miles and a third eastward of the Whale’s Back.

Coast of Massachusetts: an extension of the sand spit to the southward of Sunken ledge, Boston harbor, since the survey of 1847.

Coast of Connecticut: Luddington rocks, determined in position, about ten yards apart, one mile and a half (nautical) S.W., by compass, from New Haven light-house.

Coast of New York: Tidal currents in East river, and surface and subcurrents investigated in New York harbor, the lower bay, and on the bar.

Charleston harbor: increase of depth developed in Maffit’s channel.

Coast of Florida: a new and deeper channel discovered, leading into St. George’s sound (Apalachicola), at the eastern end of Dog island, and anchorage connected with it; shoals near the East and West passes of St. George’s sound, and a new channel found between St. George’s and St. Vincent’s islands.

Coast of California: Whiting’s rock, determined in position, near “The Brothers,” at the entrance of S. Pablo bay; a reef developed off the Contra Costa flats, San Francisco bay.

Washington Territory: a bank of three and a half fathoms, about a mile off the S.W. point of Sucia island, northern entrance of Washington sound.

AID AFFORDED TO THE LIGHT-HOUSE SYSTEM.— The survey of the coast furnishes also, as part of its direct results, this further and most valuable benefit to the navigator, in the indication of the most appropriate points upon which to establish lights, beacons, buoys, fog-bells, and whatever other constructions may be useful in giving assurance of safety, or indicating the possibility of danger.

For the judicious selection of sites for light-houses, it is necessary to be in possession not only of the hydrography along the coast, but also of the topography of the shore, and of the points which become landmarks in connection with the light-house. This information we have seen that the Coast Survey furnishes, and hence the determination of light-house sites seems to be apart of its appropriate functions. Such has been the view of the subject taken by the government; and accordingly, in 1852, the construction and general disposition of the light-houses of the coast having been confided to a Board composed of officers of elevated rank in the army and navy, with two civilians selected for their heigh scientific attainments, the examination of suitable sites for these structures was assigned to the Superintendent of the Coast Survey. In the six years that have since elapsed, preliminary surveys or examinations have been made in more than one hundred localities on the Atlantic, Gulf and Pacific coasts of the United States, and at least half of the cases reported are based upon recommendations for aids to navigation suggested by the Assistants while surveying in the respective localities.

AID AFFORDED TO THE PLANNING OF THE DEFENCE OF THE COAST.– The bearings of the Coast Survey on subjects connected with the defences of the coast, must be passed over by the Committee more briefly than their importance deserves. The eminent soldier at the head of the Engineer Corps of the Army, on whom the office of discussing them would have appropriately devolved, was on the eve of departure from the country when the preparation of this report was originally taken in hand. A few paragraphs from his letter to the late chairman, written a short time before his departure, must be accepted as the too succinct expression of his views:

“I cannot,” he says,“refrain from urging you to insist emphatically upon the very important aid that has been rendered by the Coast Survey to the system of National Sea-coast Defences, and to the improvement and preservation of harbors. For many years the Engineer Department has had no other resource than the Coast Survey for the general information necessary for the determination of the sites of new fortifications. It has often been without other resources as to local topography and hydrography. It has been enabled, by this aid, greatly to expedite the construction of defensive works of the highest necessity: and I must not omit to add, that the operations of the Coast Survey have, on some occasions, by the kind consideration of the Superintendent, been specially arranged in the order of time, and in the manner, calculated soonest to supply our necessities. In relation to the improvement and preservation of harbors, it may be said, generally, that great as the function of exhibiting the coast in its present state may be, a not less important one is the detection of its disturbances: for only on the exact knowledge of these (already found by the labors of the Survey to be great and various, and often threatening), can any judicious precautions and remedies be founded. Under the feeling of these obligations to the Coat Survey, I can hardly keep from warming up into specification and amplification– for which, however, I have no time under the arrangements which are pressing on me.”

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