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CONTENTS.

No. 10. Report on the draught of vessels which can enter the south

channel of Columbia river, by Lieut. W. A. Bartlett, U. S.

N., assistant in the Coast Survey.

No. 11. Report of the Superintendent of the Coast Survey to the Secre-

tary of the Treasury, communicating a letter from Lieut. W.

A. Bartlett, U. S. N., assistant in the Coast Survey, relating

to commerce of Columbia river.

No. 12. Report of Lieut. Com'g W. P. McArthur, U. S. N., and Lieut.
W. A. Bartlett, U. S. N., assistants in the Coast Survey, to
the Superintendent, on the lights necessary for San Francisco
bay, California, and its approaches.

No. 13. Letter of the Superintendent of the Coast Survey to the Secre-

tary of the Treasury, transmitting the report of R. D. Cutts,

esq., assistant in the Coast Survey, with sketches of his survey

of Fort Point, at the entrance of San Francisco bay, and of

Alcatraz, or Bird island, within the bay, proposed as sites for

light-houses.

No. 14. Correspondence of the Superintendent of the Coast Survey with

the Secretary of the Treasury, in relation to buoys for sunken

rocks in the harbor of San Francisco, reported by the collector

of that port.

No. 15. Report of the Superintendent of the Coast Survey to the Sec-

retary of the Treasury, on the necessity for a light-house at

Humboldt harbor, California, with report of Lieut. Com'g Jas.

Alden, U. S. N., assistant Coast Survey.

No. 16. Letter of the Superintendent of the Coast Survey to Hon. Joseph

Grinnell, of the committee on commerce, H. R., communicat-

ing a report of Lieut. W. A. Bartlett, U. S. N., assistant

Coast Survey, on the importance of a light-house at Humboldt

harbor.

No. 17. Report of the Superintendent of the Coast Survey to the Secre--

tary of the Treasury, showing the most suitable site for a

light-house at Point Conception, California.

No. 1.

U. S. COAST SURVEY,

A. D. BACHE, SUPERINTENDENT.

SAILING DIRECTIONS,

TO ACCOMPANY THE NEW CHART OF THE WESTERN COAST OF THE U. S.. First edition, published December, 1850.

For the western coast of the United States, from Monterey to Columbia river, by Lieut. Commanding W. P. McArthur, U. S. N., assistant in the Coast Survey, and Lieutenant Washington A. Bartlett, U. S. N., assistant.

From March to October the prevailing wind along the coast, and for many miles to the westward, is fresh from the northwest, being freshest from 10 a. m. to 2 p. m., and not unfrequently falling light during the night. During this season of the year the northwest wind blows with almost the regularity of a trade wind, causing a current of about a half a knot per hour along the coast, setting to the southward. During the months of August and September fogs prevail; there are no heavy gales of wind, and little or no rain.

From October to March the wind is variable, both with regard to velocity and direction; heavy gales occur from the southeast, south, and southwest, generally accompanied by protracted rain, and causing a very heavy sea and swell along the coast. The current sets generally to northward, varying in velocity with the strength of the wind.

Sailing vessels bound to the northward from Monterey, or any more northern port, during the summer season, should stand well off shore, not too close hauled, until about two hundred miles from the land, when they will be beyond the influence of the southerly current, and in a situation to take advantage of a slant of wind, which frequently occurs from the west-northwest. They would do well not to approach the land unless favored by the wind, so as to enable them to lay their course, or nearly so, until up with the latitude of the destined port.

Steamers should follow the coast from point to point as nearly as possible, always keeping within fifteen miles of the land. They will by this means shorten the distance, and frequently avoid the strong northwest winds, as they will often find it quite calm close in with the shore when there is a strong wind to seaward. Bound to the northward, in the winter season, keep as close along the land as practicable, and take every advantage of all southerly winds to make latitude. Always endeavor to make the land at least twenty or thirty miles to the southward of the destined harbor.

Bound to the southward, keep the coast in sight, and take advantage of either tack upon which the most latitude may be made, always making the land to the northward of the port in summer, and to the southward in the winter season.

For latitudes, longitudes, courses, and distances, refer to the charts. and tables.

SHEET No. 1.

BOUND INTO SAN FRANCISCO OR MONTEREY, use every opportunity to observe for latitude and longitude, so as to know the vessel's position up to the latest moment, as fogs and haze, preventing observations, prevail near the land. Allow generally for a southerly set of half a mile an hour, until within about fifty miles of land; after which, at times, it is not appreciable. With these precautions, vessels may steer boldly on, shaping a course for the South Farrallon, an islet about 250 feet high and a mile long, having 14 fathoms water, and good holding ground on the S. E. side. This islet has been recommended as the site for the outer light of San Francisco.

On approaching soundings the water becomes of a pale green color Soundings may be had in 60 to 40 fathoms, soft ooze, if approaching Punta de los Reyes. Below 40 fathoms is near the land, and the surf should be heard, if haze prevents the land from being seen. If the soundings are thirty fathoms or under, and the sea smooth, anchor with a kedge until the land becomes visible, so as to take a compass bearing, as the position cannot otherwise be relied on.

If up with the S. Farrallon and night approaching, or there are appearances of fog, anchor at the Farrallon and wait daylight, when the morning breeze will carry the vessel to the bar or pilot ground; course N. E. + E., (by compass,) 27 miles.

Inside the Farrallones the "set" is generally towards the north shore, but it may be approached without risk, keeping outside of the KELP, which marks rocks under water.

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