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APPENDIX No. 43.

Report of the Superintendent of the Coast Survey to the Secretary of the Treasury, recommending a light-house at Point Loma, near San Diego, California; with the report of Sub-Assistant A. M. Harrison on the

same.

COAST SURVEY OFFICE,

November 22, 1851.

SIR: In conformity with the instructions of the Treasury Department, I have caused a survey to be made for the sight of a light-house at Point Loma, near San Diego, California, for which an appropriation was made by act of Congress approved September 28, 1850. I send herewith a sketch, showing the locality proposed for the light, and its relations to the harbor of San Diego and its approaches; also, a subsketch, on a large scale, giving the character of the site more in detail. In a few weeks an engraved harbor chart of San Diego will be transmitted, to take. the place of these sketches, or as supplementary to them.

The light which is recommended is one of the first order, or a seacoast light, to be placed on the bluff in the position marked, in a tower (say) twenty feet high. The range will thus be 31.7 statute miles, and the light will be visible beyond the Coronados, and over a sector of the horizon of about 1870.

A small harbor-light is further recommended on Ballast point, at the place marked in the sketch, as a leading light up the bay. Its elevation may be fifteen feet.

I append the report of Sub-Assistant A. M. Harrison, by whom the plane table survey of Point Loma was made. The survey of the harbor was made by Assistant R. D. Cutts, of the coast survey.

The considerable height of the point at which this light-house is to be placed induced me to withhold the report of Mr. Harrison, and any recommendation concerning it, until I had consulted him as to the probability of interference from fog. He reaffirms his opinion of the propriety of the site, after considering this objection.

In recommending lights for the western coast, I have not advised that any of them be revolving lights, except in the case of Point Conception, conceiving that at present, until facilities for repairs of machinery and the number of lights are increased, it is inexpedient and unnecessary to resort to such a distinction.

Very respectfully, yours,

A. D. BACHE,

Superintendent United States Coast Survey.

Hon. THOMAS CORWIN,
Secretary of the Treasury.

LA PLAYA, NEAR SAN DIEGO, CALIFORNIA,

June 2, 1851.

DEAR SIR: This report accompanies a tracing from the plane table map of the bay of San Diego, including Point Loma, the proposed

light-house site, and La Playa, (the port of San Diego,) on a scale of

10000.

Point Loma is a long, narrow strip of land, extending in a southerly direction about 23 miles from the Playa, and is composed of a chain of abrupt and broken hills, varying from 200 to 400 feet in height, cut with deep, narrow, and in many places precipitous gorges. On the western side the shore is perpendicular, and varies from twenty-two to ninety feet in height; while on the eastern shore of the Playa to Ballast point, (a narrow low spit, formed of large pebbles, running out from Point Loma, and forming the western side of the entrance,) the shore is bluffy, and not generally as high as the opposite one. To the south of Ballast point the shore is still bluffy, and increases gradually, until it reaches the extreme point. At this place the hills jut boldly upon the sea, forming a very steep bluff, three hundred feet in height. The hills are composed mainly of coarse modern sandstone, and are covered with a growth of low bushes, red wood, and artemisia, interspersed with three or four varieties of cactus. Landing is practicable, in calm weather, at almost any part of the point; but the hills are so precipitous that it would be almost impossible to transport any building materials up their sides.

The position for a light-house, which I have marked upon the chart by a red circle, I recommend for the reason of its superior elevation, the large view it commands to seaward, its good foundation, and its level surface. It is four hundred and twenty-two feet high.

The distance at which the rays of light would touch the horizon of the ocean from a light-house twenty feet high, located at this site, would be thirty-two and four-tenths statute miles.

It commands an extent of horizon to seaward of 1870. In erecting a light-house on this point, the materials should be landed at the Playa, and then could be easily carried to the point along the top of the range of hills. There is a path extending the whole distance, and, with a little cutting of the bushes, it could be made practicable for mules. It would be necessary to bring the materials for building purposes from some other port, as there is nothing in this region which could be turned to advantage.

There is no water nearer than San Diego, five miles distant from the Playa. It is obtained from San Diego river, and brought down in casks. Some men are at present boring an Artesian well at the Playa, but success is very doubtful. The land is not favorable for cultivation.

The entrance to the bay is so narrow, and Ballast point is so low, that I think a secondary light on the end of it would be advisable. The extremity of the point is composed of large, round pebbles, similar to our paving stones, and the foundation is quite hard. I have marked the point upon the tracing.

Since our stay here, fogs have been frequent and heavy, and I think it would be advisable to place a fog-signal upon the bluff at the end of the point. If it is to work by the action of the waves, it could be

placed upon a reef running S. by W. from the end of Point Loma, where there is always a swell, even in the calmest weather.

Respectfully submitted.

Professor A. D. BACHE,

A. M. HARRISON.

Superintendent United States Coast Survey.

APPENDIX No. 44.

Letter of the Superintendent of the Coast Survey to the Secretary of the Treasury, transmitting the report of Sub-Assistant A. M. Harrison, of a survey of Cape Disappointment, or Hancock, for location of a light-house, and communication of Lieutenant Bartlett, U. S. N., assistant in coast survey, on same subject.

COAST SURVEY STATION, NEAR ALFRED, ME.,

September 29, 1851.

SIR: I have the honor to transmit, in pursuance of the instructions of the department, a minute survey of Cape Disappointment, or Hancock, at the entrance to Columbia river, Oregon, for the location of the lighthouse for which appropriations have been made. To the report and sketch of Assistant A. M. Harrison I add a proof-sheet of the preliminary survey of the entrance, to show in a general way the localities referred to. I have also annexed a report by Lieutenant Bartlett, U. S. navy, assistant in the coast survey, in relation to this same light, which contains suggestions in reference to the kind of structure to be erected there. I approve the recommendations of Assistant Harrison of the site marked on his map for the light-house, and of the elevation of forty feet, which he proposes for the light. It should be a seacoast light of the first class, and will be visible nearly twenty-five miles.

I would recommend that so much of the adjacent woods should be removed as will render the establishment secure from the near approach of fire.

Very respectfully, yours,

A. D. BACHE, Superintendent U. S. Coast Survey.

Hon. THOMAS CORWIN,

Secretary of the Treasury.

U.S. COAST SURVEY STATION, CAPE HANCOCK,

Mouth of Columbia River, Oregon, July 28, 1851. DEAR SIR: I send with this report a tracing of Cape Hancock, or Disappointment, on a scale of 10. It embraces the proposed lighthouse site and three miles of the shore. Cape Hancock, forming the northern point of the entrance to Columbia river, is a bold, narrow promontory of basaltic rock, projecting into the sea in a curve from the north around by the west to the south.

The extremity of the cape is formed of a range of hills, varying from one hundred and fifty to two hundred and eighty feet in height, generally narrow at the summits. On the outer faces these hills are covered with rank, high, thick grass and weeds, and slope abruptly to different heights; then, falling perpendicularly, present to the ocean an irregular wall of rock, intersected at one or two points by deep inlets, into which the sea flows during flood tides. On the inner side the slope is more gradual, but in most places also steep, and from the top of the ridge down to the water's edge, covered with tall pines, and a dense and occasionally impenetrable undergrowth of bushes; the salmon berry, fern, and salal being the principal kinds. The soil is rich, and covered to the depth of a foot, and in some places more, with a light, yielding carpet of decayed and decaying leaves and branches, the annual deposite of the trees and bushes above.

The cape forms the western shore of Baker's bay, which affords good anchorage in six and three fathoms.

The position which I think most advisable for the location of a lighthouse, and which I have marked upon the tracing by a black circle, I recommend for the following reasons:

Height. Although ninety-five feet lower than the hill upon which the observatory is situated, (which is the highest on the end of the cape,) I think it has the advantage from the fact that the fog banks, during their prevalence, frequently, and in fact generally, rest upon and above the summits of the most elevated hills; while those below are clear and unobscured. So I am informed by persons who sail in and out of the river. Light-house hill is one hundred and ninety-two feet high; Observatory hill two hundred and eighty-seven feet.

Command to Seaward. The angle commanded to seaward by a light placed as recommended would be much greater than one on Observatory hill, unless the government chose to go to the expense of time and money in felling a large quantity of trees to the northward, and those, like all trees of Oregon, of no ordinary size. A person standing on the proposed site commands a view to seaward of one hundred and thirty four degrees.

Form. Upon the summit it is broader, and would require less digging and grading to secure a sufficiently large foundation. In fact a light-house could not be erected upon the narrow top of Observatory hill without a great deal of trouble and expense on this account. In digging I find stone at the depth of two feet.

The best point at which to land materials for building purposes is the little cove I have marked ("a") upon the tracing. A road which was cut for carrying up the observatory would suffice to get upon Observatory hill; but the path between the Observatory and Light-house hill runs along a narrow ridge. I have marked it upon the tracing by a black line. I think it would be advisable to cut a road directly from the cove to Light-house hill, a distance of about 440 metres (481 yards.) The cove ("a") in which our camp is pitched is a good position for a house, being, by the present path, fifteen minutes' walk from Lighthouse hill. A spring of fine water runs in a continual stream from the rocks, a few metres from camp, and there is sufficient ground for a

small vegetable garden. A house once stood here, but was destroyed by fire.

The site for a city has been laid out about two miles from the point, under the title of Pacific city.

The house which you see upon the tracing was erected by the Hudson's Bay Company, and is occupied by a half-breed and his family. He has quite a good garden.

The distance at which a light, forty feet high, located at the site, would be visible, is twenty-five statute miles, nearly. Respectfully submitted by your obedient servant, A. M. HARRISON,

Prof. A. D. BACHE,

Sub-Assistant Coast Survey.

Sup't U. S. Coast Survey, Washington.

Report of Lieutenant Washington A. Bartlett, United States navy, assistant in coast survey, to the Superintendent, in relation to a light-house at Cape Hancock, or Disappointment, entrance to Columbia river.

WASHINGTON, November 29, 1850.

SIR: In answer to your inquiries as to the character of the lighthouse which should be erected at Cape Hancock, or Disappointment, at the mouth of the Columbia river, Oregon Territory, and for information as to the locality on which it should be placed, &c.

I have the honor to state, that Cape Hancock, or Disappointment, at the mouth of the Columbia river, Oregon Territory, where it is proposed by a late act of Congress to erect the principal light-house for that river, is a bold cliff of columnar basalt, rising perpendicularly from the sea to variable heights of from two hundred to three hundred feet, terminating in unequal rolling summits, covered with a rich and fertile soil.

The summits vary also in width from ten to fifty feet at the apex, whence they slope by a quick descent to the northward; the northern or in-shore face of the hills being covered by a dense growth of gigantic pine, alder, and other trees, with a thick growth of vines, "salmon berry," and other shrubbery.

The summit of the sea cliffs (which are not covered by the forest) is the proper position for locating the light-house; say within two to four hundred yards to the westward of "Broom station," as given on our triangulation of the river. Should the tower be placed there, it will show the light from the lantern around three-fourths of the horizon without the necessity of felling the trees to the northward.

In this position the base of the tower will be about two hundred and fifty feet above high-water mark; and should the tower be raised forty feet to the deck of the lantern, (and in my opinion it should not be less,) on a base of sixteen feet in diameter, it will be a prominent landmark for making the cape in the daytime.

The lantern, or light, which is to be placed on the tower should be of a power not less than the best light on Navesink; in other words, a marine light of the first power.

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