(NNE. 5% E. mag.), distant 5 miles. Then steer 0° true (N. by W. 12 W. mag.) for 22 miles for the whistle buoy and thence to the anchorage off the wharf, as desired.

From northward.—From a position 2 miles southwestward from the Ano Nuevo Island Lighthouse steer 132° true (SE. by E. % E. mag.), and give the coast a berth of over 11⁄2 miles. Continue this course 15 miles, and when Santa Cruz Lighthouse bears 76° true (NE. by E. % E. mag.) steer 84° true (ENE. mag.) for the whistling buoy and pass nearly 1 mile southward of the light. When the lighthouse is abeam, round up to the anchorage off the wharf.

SAN FRANCISCO BAY AND APPROACHES (CHARTS 5530, 5531, 5532, 5533, 5534, 5535)

The approaches to San Francisco Bay are included in the area bounded on the north by Point Reyes, on the west by the Farallones, and on the south by Point San Pedro. This body of water, known as the Gulf of the Farallones, is about 35 miles long in a northwest and southeast direction, with a greatest width of 23 miles, and communicates eastward by a narrow entrance, the Golden Gate, with San Francisco Bay. The prominent and easily distinguished landfalls, and the numerous natural and artificial aids, make the navigation of the approaches comparatively simple in clear weather. In thick weather the currents, variable in direction and velocity, render the approaches difficult and dangerous, and strangers should either lie off and wait for clear weather or take a pilot. Point Reyes, Mount Tamalpais, the Farallones, Point San Pedro, and Montara Mountain are all prominent in clear weather, and can frequently be used to locate a vessel's position when the lower land near the beach is shut in by fog or haze. A flashing white aviation beacon on Mount Diablo, bearing 83° true (NE. by E. 34 E. mag.), distant 30 miles from the Golden Gate, is operated from sunset to sunrise by private interests and should be visible in clear weather from vessels approaching San Francisco Harbor. Drakes Bay, eastward of Point Reyes, and Bolinas Bay, eastward of Duxbury Point, are open bights affording shelter in northwesterly weather, but exposed in southerly weather.

Point Reyes is a bold, dark, rocky headland, nearly 600 feet (183 m) high, and the western and higher extremity of a ridge running east and west for 3 miles. There is low land northward of it, so that from northward and southward it is usually made as an island, and also from seaward in hazy weather. It is visible for over 25 miles, and can be seen off Point Bonita, the northern headland at the entrance to the Golden Gate.

Two sunken rocks with about 3 feet (0.9 m) over them at mean lower low water, lie about 275 yards west of the light. These rocks break with a moderate swell.

Point Reyes Lighthouse, situated on the western extremity of the point, is a white pyramidal tower. The light is flashing white (flash 1.5 second, eclipse 3.5 seconds), 294 feet (90 m) above the water, and visible 24 miles. The fog signal, an air diaphone (blast 5 seconds, silent 40 seconds), is established on the western pitch of Point Reyes about 130 feet (40 m) below the lighthouse. The fog signal sounds 5 or 6 short blasts and a blast of 15 seconds to warn the

Coast Guard crew when vessels are in distress. A storm warning display and seacoast telegraph and reporting station is situated on the northwesterly end of the high ridge back of the lighthouse. The station is equipped for signaling with the international code, and will transmit messages of passing vessels. There is a telephone line to San Francisco.

A radio direction finder station, call letters NLG, operated by the United States Navy, is located on the beach 234 miles northward from the light. See page 13.

Mount Tamalpais, about 7 miles northward from Point Bonita, is a prominent mountain 2,604 feet (794 m) high. In clear weather it is visible for over 60 miles. From southward and westward it shows three summits, of which the western is the highest and the eastern the sharpest. It is covered with bushes and scrub trees, giving it a dark appearance, which contrasts strongly with the surrounding hills, especially in summer, when the latter assume a light reddish color.

The Farallones are a group of rocky islets extending about 7 miles in a northwest and southeast direction. The Southeast Farallon, the largest of the group, lies 18 miles 177° true (S. by E. % E. mag.) from Point Reyes Lighthouse, and 23 miles 252° true (SW. 34 W. mag.) from Point Bonita. It is really two islands, separated by a narrow gorge impassable even for boats. The eastern one is the larger, pyramidal in shape, 350 feet (107 m) high and surmounted by Farallon Lighthouse, a white conical tower. The light is a flashing white every 20 seconds, flash 2.7 seconds, eclipse 17.3 seconds. The fog signal is an air diaphone, sounding a group of 3 blasts of 2 seconds duration every 60 seconds, silent intervals 4, 1, and 49 seconds.

The fog signal, keeper's dwelling, and Navy radio direction finder station are located on the lowland on the south side, and the fog signal can seldom be heard northwestward of the island. The call letters for the radio direction finder station are NPI. A radiobeacon has been established at the light. See Light List Pacific Coast for details.

Farallones radio direction finder station, together with the Point Reyes and Montara Point stations, give the navigator an excellent opportunity to frequently verify his position by three radio bearings in approaching the Golden Gate in foggy weather, and it is an oppor- . tunity that should not be neglected.

The western and smaller island known as Maintop is 220 feet (67 m) high. There are several rocky islets lying close-to, the largest of which, Sugarloaf, 200 feet (61 m) high, lies northwestward from the lighthouse and forms a small cove where anchorage can be had in 8 fathoms (14.6 m) on the line between the points, and having a boat landing on a small sand beach in it. A submarine cable is laid from this cove to Drakes Bay. There is another boat landing on the south side of the island. Both are marked by derricks and landing stages. Hurst Shoal lies 5 mile 152° true (SE. % E. mag.) from the lighthouse. It is of small extent, with a least depth of 4 fathoms (7.3 m), and breaks only in heavy weather. The Middle Farallon lies 24 miles 319° true (NW. by W. 14 W. mag.) from the lighthouse. It is a single black rock 50 yards in diameter

and 20 feet (6.1 m) high. A rock, with 51⁄2 fathoms (10 m) over it, lies 1 mile southwestward from it. The North Farallones lie 612 miles 311° true (WNW. mag.) from the lighthouse, and 14 miles 195° true (S. 14 E. mag.) from Point Reyes. They consist of two clusters of bare, precipitous islets and rocks extending in a west-northwest and east-southeast direction for 7% mile, with an average width of 1/4 mile. The highest rock, 155 feet (47 m), is in the southeastern group. Noonday Rock, with 14 feet (4.3 m) over it, lies 3 miles 296° true (W. 5% N. mag.) from the northernmost rock of the North Farallones and 14 miles 209° true (S. by W. mag.) from Point Reyes. It rises abruptly from depths of 20 fathoms (37 m) and over, and is the principal danger in approaching from northward. It is marked by a red and black horizontally striped whistle buoy placed in about 26 fathoms (48 m), 400 yards southwestward from the rock, which is the shoalest point of Fanny Shoal; the latter is about 2 miles in extent, having depths of 20 to 30 fathoms (37 to 55 m).

Noonday Rock derives its name from the clipper ship of that name which struck it in 1862 and within an hour sank in 40 fathoms (73 m).

Point San Pedro is described on page 90.

From Point San Pedro to Point Lobos, the southern headland at the entrance, the coast extends 111⁄2 miles in a north-northwesterly direction, the first 8 miles consisting of whitish bluffs which at a point 5 miles northward of Point San Pedro reach a height of 600 feet (183 m). Between Point Lobos and these bluffs is a broad, sand beach extending back to high sand dunes, the latter terminating abruptly at Golden Gate Park 112 miles southward of Point Lobos. These whitish sand dunes are prominent from a considerable distance seaward.

A wooden tower on the brow of the hill 575 feet (175 m) above the water and 51⁄2 miles northward of Point San Pedro is prominent. Point Lobos is high, rocky, and rounding, with black, rugged cliffs at its base. A marine lookout and reporting station is on the ridge back of the point, and the summit has upon it several houses and a large water tank on a high scaffolding. Seal Rocks, a group of high, rocky islets, lie close under its western face. The Cliff House and a number of other prominent buildings are situated on and near the southern point of its western face.

From Point Reyes to Point Bonita the coast extends in a general easterly direction for 26 miles. From the former point the coast trends eastward for about 3 miles and then bends sharply northward and eastward forming Drakes Bay.

Drakes Bay (chart 5599) affords shelter in northwesterly weather in 5 to 6 fathoms (9.1 to 11.0 m), sandy bottom. From the western headland, which is the eastern end of the ridge forming Point Reyes, high, white cliffs extend northward and eastward in a gentle curve for 6 miles, terminating in high, white sand dunes. Several lagoons on the northern shore empty through a common channel which is navigable by light-draft vessels with local knowledge. The western point is 230 feet (70 m) high, with a detached rock lying close under the eastern extremity. A reef, which breaks in moderate weather, extends more than 2 mile eastward from the point. The harbor is

used extensively by vessels in heavy northwesterly weather. Shelter has been obtained in southeasterly weather, close under the western point, in 4 fathoms (7.3 m), sticky bottom, the force of the swell being broken by the reef off the point; this anchorage is not recommended. No directions for entering are necessary, further than to give the point a berth of not less than 3/4 mile to avoid the reef previously mentioned. The telegraph cable to Farallon Island is laid close around the inside of the reef off the point and landed abreast the first depression in the ridge westward. Vessels should avoid anchoring near it.

The Point Reyes Coast Guard Station is located on the west side of Drakes Bay, 25% miles eastward of Point Reyes Light.

From the sand dunes near the eastern part of the bight, rocky cliffs 100 to 200 feet (30.5 to 61 m) high extend eastward and southward for 6 miles to Double Point.

The southern cliff has a rock close under the point and nearly connected with it at low water.

From Double Point to Bolinas Point, 311⁄2 miles, the coast is bold with high, rocky cliffs bordered by narrow sand beaches and no outlying dangers.

Bolinas Point, 160 feet (49 m) high, is the western point of the comparatively level tableland extending eastward to Bolinas Lagoon. Owing to its proximity to Duxbury Point it is not particularly prominent. The radio towers of a large commercial transmitting station, 5% mile north of the point, are prominent.

Duxbury Point, 160 feet (49 m) high and yellowish in color, is 5 miles southeastward from Double Point and 912 miles northwestward from Point Bonita. It is the southern extremity of the tableland westward of Bolinas Lagoon.

Duxbury Reef, a dangerous reef upon which many vessels have been lost, is long, narrow, and partly bare at low water. It extends 114 miles southeastward from Duxbury Point. A ledge from 5 to 6 fathoms (9.1 to 11 m) over it extends southward from the reef, its outer end lying 1% miles 183° true (S. by E. % mag.) from the point.

Duxbury Reef lighted whistle buoy is placed in 12 fathoms (21.9 m), 2 miles 172° true (SSE. % E. mag.) from Duxbury Point. Great care should be exercised in passing this reef, and vessels should not pass to the northward of the buoy.

Bolinas Bay lies immediately eastward of Duxbury Point. It is an open bight 312 miles long between Duxbury and Rocky Points and a little over 1 mile wide. It affords shelter in northwesterly weather in 4 to 6 fathoms (7.3 to 11 m), sandy bottom, with Duxbury Point bearing about W. by S. mag. distant 111⁄2 miles, but is little used. A rock awash at low water, with another rock awash 250 yards northward of it, lies 3/4 mile 96° true (E. by N. mag.) from Duxbury Point. A rock, with 2 feet (0.6 m) over it, lies 150 yards westward of the first rock. A rock awash, and a rock having 13 feet (4 m) over it 250 yards northeastward, lies nearly 1 miles 138° true SE. by E. 3 mag.) from Duxbury Point. No directions are necessary other than to keep clear of Duxbury Reef and the dangers previously described.

Bolinas Lagoon is separated from the bay by a narrow strip of sandy beach that is cut by a narrow shifting channel near the bluffs about the middle of the bight. The lagoon is shoal and of little commercial importance. It is entered by small, light-draft vessels with local knowledge. In October 1933 the controlling depth at the entrance was reported as 3 feet (0.9 m) at mean lower low water. The village of Bolinas, population 125 (1930 census), is located a short distance inside the entrance on the western shore. A Coast Guard station is located at Bolinas.

Rocky Point, 31⁄2 miles eastward from Duxbury Point, is 100 feet (30.5 m) high and shelving. Numerous detached rocks lie within 200 yards of the cliffs, which on the southern side of the point are high and precipitous.

From Rocky Point to Point Bonita the coast is very rugged and broken. The cliffs, which are the seaward termination of spurs from Mount Tamalpais, rise to heights of over 500 feet (152 m) and are intersected by deep, narrow valleys stretching inland.

Point Bonita, the northern point at the entrance, is a black, sharp, narrow, precipitous cliff 100 feet (30.5 m) high, increasing in height to 300 feet (91 m) on its seaward face 1/4 mile northward. From northwestward it shows as three heads, the southern one being cut down to form a place for Bonita Point Lighthouse, a white tower. The light is group flashing white (flash 1 second, eclipse 2 seconds, flash 2 seconds, eclipse 15 seconds). The fog signal is an air diaphone (blast 1 second, silent 2 seconds, blast 2 seconds, silent 25 seconds), and sounds 5 or 6 short blasts, and blast of 15 seconds duration, to warn Coast Guard crews when vessels are in distress. In the summer the cliffs are white with bird droppings, but the first heavy rain restores them to their natural black color. There are a few detached rocks surrounding the point, but these do not extend over 200 yards offshore.

The bar outside the entrance is semicircular in form, the area, with 6 fathoms (11 m) or less, extending from a point 1/2 mile westward from Point Bonita to a point nearly 1 mile offshore 3 miles southward from Point Lobos. The extreme outer point is 52 miles southwestward from Point Bonita. This is also the narrowest part, the distance between the inner and outer 6-fathom (11 m) curves being little over 1/4 mile. The northern part is the shoalest and is known as Fourfathom Bank, within the limits of which is a small area of less than 4 fathoms (7.3 m) locally known as the "Potato Patch Shoal", which name is said to have originated from the fact that schooners from Bodega Bay frequently lost their deck loads of potatoes while crossing it. Over the remainder of the bar (except the dredged portion of the Main Ship Channel) the depths range from 31 to 36 feet (9.4 to 11 m), the deepest water being found near the southern end, which is nearly 1 mile wide. The depths as a rule vary but little from year to year, with a slight tendency to increase. The depths in approaching are regular and decrease gradually to about 8 fathoms (14.6 m) and then abruptly to the crest of the bar