should not be attempted except with an experienced boat crew. Boats usually approach the beach with an anchor to seaward and float whatever freight they have through the surf. These remarks apply also to landings on the shore anywhere on the Bering Sea side. The lighthouse keeper will advise landing conditions and direct the boat crew to the proper landing.

Cape Sarichef Lighthouse looking about northeast by east (magnetic).

CAPE SARICHEF, the western end of Unimak Island, is the eastern point at the northwestern entrance to Unimak Pass. The cape is about 100 feet (30 m) high, with steep grassy sides, and the land back of the cape forms a table land and slopes gradually upward to Pogromni Volcano (p. 307). There is a black lava bed along the beach south of the cape, and 2 miles south of the cape there is a flat rock barely detached from the coast.

A bank of black sand extends about 3 miles westward from Cape Sarichef; there are depths of 10 to 15 fathoms (18.3 to 27.4 m) over it, and there are heavy tide rips, overfalls, and eddies; the current reaches an estimated force of 2 knots. The bank appears to be an extension in a west-northwesterly direction of the old lava flow which may be seen 1 mile southward of Cape Sarichef Lighthouse. No dangerous rocks were found. In 1924 the survey ship Pioneer anchored on this bank with calm weather while strong winds were blowing a short distance away both north and south of the anchorage. A reef is reported to extend about 3/4 mile from the shore about 1 mile northwestward from the lighthouse.

The Chelan anchored in the bight just northwestward of Middle Point, but this is recommended only as a temporary anchorage because of the current and swirls encountered.

Cape Sarichef Lighthouse, a white tower (black lantern) on an octagonal building, is located on the summit of the cliff. There are a number of buildings near it. The light is occulting white, light 25 seconds, eclipse 5 seconds, 126 feet (38 m) above high water, and visible 17 miles. It is obscured from 22312° true to 1812° true, the bearings being from seaward. The fog signal is a first-class air

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siren, blast 3 seconds, silent 5 seconds, blast 3 seconds, silent 49 seconds. The light is discontinued from December 1 to March 1, except when vessels are known to be in the vicinity.

Shishaldin Volcano and other high peaks on Unimak Island used as landmarks in clear weather are described on page 306.

UGAMAK ISLAND (chart 8860), on the south side of Unimak Pass in entering from the Pacific, is the eastern one of the Krenitzin Islands which extend westward to Akutan Pass. The island is rugged with a sharp peak, elevation 1,041 feet (317 m), at the eastern end; when viewed from the southeastward, several pinnacles protrude from the slope to this peak giving an extremely rugged appearance. Near the middle of the island is a knob 905 feet (276 m) high. The island is mainly tundra covered. The shore is backed by bluffs 50 to 1,000 feet (15.2 to 305 m) high. Of the southeast point of the island is a conical pinnacle, 310 feet (94 m) high, which is separated from the island by a narrow gorge 10 to 15 yards wide. About 1/4 mile off the southeast end are two rocks awash, generally marked by breakers. Twin grassy islets, the northern one of which is 127 feet (39 m) high, lie 5% mile southward of the east point of Ugamak Bay, a cove on the south side of Ugamak Island. The islets are separated by a deep gorge and appear as one islet. The collective name of Round Island is applied to them.

Strong currents sweep around the east end of Ugamak Island and heavy tide rips occur here. It is advisable to give this end of the island a berth of about 2 miles.

Aiktak Island 558 feet (170 m) high lies southward of the western part of Ugamak Island, the two islands being separated by a pass 1/2 mile wide and 6 to 10 fathoms (10.1 to 18.2 m) deep. Small vessels use this pass for temporary anchorage, but moderately strong currents make the anchorage rather unfavorable. On the south side of Aiktak Island are sheer bluffs, the tops of which approach the highest parts of the island. The islet off the northeast end is grass covered and less than 100 feet (30 m) in elevation.

Temporary anchorage in northerly weather may be found in Ugamak Bay in depths of about 16 fathoms (29.3 m) about 1/2 mile from shore. In southerly weather, some shelter may be found on the north side in a small bight 111⁄2 miles west of the east end of the island in 16 to 20 fathoms (29.3 to 37 m) 1/4 mile from shore.

Akun Island, on the west side of the approach to Unimak Pass from the Bering Sea, is described on page 318.

DIRECTIONS, Unimak Pass (chart 8860). In the directions following no allowance has been made for the tidal currents, which have considerable velocity in Unimak Pass; this should be kept in mind in order to make the courses good.

Emerging from the inside route along the Alaska Peninsula at Cape Pankof, the directions for continuing to the westward through Unimak Pass to Unalaska will be found in the table of courses and distances on page 32.

Approaching Unimak Pass from the Pacific.-A survey of this approach including Davidson Bank, in much greater detail than charted at the present time (1937), is in progress. A larger number of soundings on the chart to indicate more definitely the limits and

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depths of the banks and deeps will materially aid vessels in thick weather navigation, particularly if the vessel be equipped with echo sounding apparatus. (See appendix p. 468).

Care must be taken to avoid the Sanak Reefs and Aleks Rock (p. 298). A good rule is to make longitude 164° W. while still south of latitude 54° N. and then stand northwestward to make Seal Cape. Approaching Davidson Bank from seaward, southeastward of Unimak Pass, the depths decrease rapidly from deep water to the 50-fathom (91 m) curve marking the seaward edge of the bank. The current runs westerly; with an easterly wind it reaches a strength of 34 knot. It runs south of west when the wind is north of east, and runs north of west when the wind is south of east. Along the 100fathom (183 m) curve it reaches a strength of more than 1 knot. Tide rips are often seen here.

Crossing Davidson Bank the depths vary between 35 and 50 fathoms (64 and 91 m). At times there is a marked change in the color of the water from blue to green when passing from deep water to the bank.

Along the shore of Unimak Island, west of Cape Lutke, no dangers were found more than 0.4 mile from the beach. In thick weather, when approaching Scotch Cap Light from the eastward, the 30fathom (55 m) depth curve is a good guide and may be followed from Cape Lutke to Seal Cape. At Seal Cape the 30-fathom (55 m) curve is 1 mile from shore and continues 270° true to a point 114 miles south of Scotch Cap Light. West of the light the 30-fathom (55 m) curve is irregular and difficult to follow. Between Cape Lutke and Scotch Cap Light, the 30-fathom (55 m) curve is quite definite and regular and follows the general trend of the coast. At no point is it more than 12 miles or less than 1 mile from shore, and this knowledge should prove of value to a vessel in this region in thick weather.

South of Unimak Pass there is a basin or tongue of deeper water the outline of which has not yet been fully determined, so that depths of 50 fathoms (91 m) may be met with when 5 miles southward of Scotch Cap Light.

In the vicinity of Seal Cape the coast is bold and may be approached with caution close enough (from 12 to 1/4 mile) in moderately thick weather to be seen and to be followed until some point is recognized by which the vessel's position may be known. A vessel should first be sure of her position before attempting to enter Unimak Pass and in thick weather should not attempt the other passes. Vessels approaching Unimak Pass on a great circle course should verify their position before porceeding far on soundings. A northeaster will augment the prevailing southwesterly current along the Alaska Peninsula. In recent years several large steamers, intending to approach the pass, have been wrecked on Ugamak and Avatanak Islands.

If the weather is very clear the mountains of Unimak Island may be seen and recognized and the course shaped for Unimak Pass; but under ordinary conditions Promontory Hill back of Seal Cape, Tigalda Island, or Ugamak Island, will be the first land sighted.

If Tigalda Island is sighted at a distance when approaching Unimak Pass, it will appear as a number of small detached islands, but

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when seen closer to, it is one island with six distinct short mountain ridges or peaks.

A 355° true course heading for Pogromni Volcano will lead nearly for Seal Cape, passing about 4 miles eastward of Ugamak Island.

Some navigators prefer to stand farther to the westward than longitude 164° W., in approaching from seaward, so as to sight Tigalda Island or Úgamak Island (p. 314). These islands often show when Unimak Island is fogged in.

The comparatively low land in the depression on the middle part of Avatanak Island (p. 316) is often clear when no other land is showing, especially in northerly weather. There are many grotesque irregularities of the surface making it easy to identify the locality. If approaching the land from the southward, this stretch probably offers the best chance for identification of surroundings, especially since it is easy of approach and comparatively free from current.

Surveys show a uniform gradual shoaling from the 100-fathom curve (20 to 25 miles offshore) in the Pacific to the vicinity of the chain of islands extending southwestward from Unimak Pass to Rootok Island. Approaching these islands on soundings, therefore, is feasible provided that care is exercised to avoid projecting ledges.

Through Unimak Pass.-If the land is recognized in the vicinity of Seal Cape, a vessel may stand westward, following the beach at a distance of 3/4 mile or more until Scotch Cap Lighthouse or Scotch Cap is made and recognized. With Scotch Cap Lighthouse bearing 17 true (N. mag.), distant 1 to 2 miles, steer 287° true (W. mag.) for 6 miles, and then steer 332° true (NW. mag.), which should give the coast of Unimak Island a berth of about 21/2 miles, and the course made good for about 12 miles should lead to a position 6 miles 253° true from Cape Sarichef Lighthouse.

In foggy weather a vessel should guard against being set on Tangginak Island (p. 318) by an ebb current drawing into Avatanak Strait. A 4 fathoms shoal (7.3 m) was located (in 1938) about 43⁄4 miles northward of Tanginak Island.

In coming from southeastward, when Ugamak Island is sighted, shape the course to pass about 2 miles northeastward of it, and then: From a position 2 miles 62° true (NE. mag.) from the northeast end of Ugamak Island make good a 321° true course for 10 miles to a position with Scotch Cap Lighthouse bearing 72° true, distant 51⁄2 miles. Then steer 332° true, with the northeastern end of Ugamak Island astern, and give the coast of Unimak Island a berth of about 212 miles; this course made good for 131⁄2 miles should lead to a position with Cape Sarichef Lighthouse bearing 72° true, distant 6 miles. Vessels equipped with a radio direction finder will be aided in making the approach to Unimak Pass by taking bearings on the radiobeacon at Scotch Cap Lighthouse. Cross bearings on Dutch Harbor station (NPR) may be found useful. The keeper at Cape Sarichef has a radio telephone transmitter and keeps daily schedules with Dutch Harbor, and schedules for testing Scotch Cap radiobeacon may be made in advance through Dutch Harbor.

Ugamak Strait, between Ugamak Island with Aiktak Island (p. 311) on the north and Kaligagan Island on the south, has a width of 3 miles. A detached shoal of 10 fathoms (18.3 m) was found in the northwestern end of the strait. Between this shoal and the west end of Ugamak Island depths of 18 to 25 fathoms (33 to 46 m) were found and the ledge which was reported and previously charted here was not disclosed; however, at certain stages of the tide, heavy tide rips occur in this area.

The following course has been used: From a position 12 miles southward of Aiktak Island, make good a 288° true course heading approximately for the south side of the 1,600-foot headland on the northeast end of Akun Island, and pass about 114 miles northward of the northernmost rock north of Tigalda Island. The current which attains a velocity of 3.8 knots or more sets across this course and allowance must be made for it to make the course good.

TIGALDA ISLAND, one of the Krenitzin Group, has its south side in latitude 54°04' N. The island is 11 miles long, and consists of six mountain ridges 1,200 to 1,800 feet (366 to 549 m) high, separated by low valleys having a northwesterly direction. The island as others in this locality is covered with tundra and grass. The western end of the island is comparatively low. Kaligagan Island, lying in Ugamak Strait 3/4 mile off the northeast end of Tigalda Island, is 3/4 mile long and 478 feet (146 m) high. There is a shack at the head of the small bight at the northwest end of Kaligagan Island.

A large number of bare rocks or islets extend 21/2 miles westward and northwestward of Kaligagan Island. The northernmost, about 60 feet (18.3 m) high is the highest and lies about 134 miles north of the Tigalda Island shore. Passages between groups of these rocks are deep and safe for small craft. In rounding the east end of Tigalda Island small craft should enter the passage between Kaligagan and Tigalda Islands heading for the innermost of the small rocky islets on a course of 298° true, to a point 250 yards off the northeast point of Tigalda Island, then steer 278° true for 1/2 mile until abeam of the western extremity of largest islet of the inner group, then steer .290° true 1% miles to the middle of the passage (3% mile wide) between two of the westerly groups of islets. On this course the northeast point of Tigalda Island is directly astern. In entering Tigalda Bay from this point care should be taken to avoid a group of rocks awash extending 270 yards off the north side of the entrance point of the bay. These rocks are marked by thick kelp. Currents in the passage between Kaligagan and Tigalda Islands are approximately half as strong as in the main passage of Ugamak Strait and currents are present among the groups of islets. Allowance should be made for these currents in making the courses good.

Tigalda Bay, on the north side of Tigalda Island, 3 miles from its eastern end, is a sheltered anchorage, except from northwest winds. The bay is about 5% mile wide and 112 miles long in a 107° true (E. mag.) direction, and has depths of 8 to 10 fathoms (14.6 to 18.3 m), rocky bottom. On account of the poor holding bottom, the anchorage is not secure in strong winds. An anchorage off the entrance to the bay in 12 to 15 fathoms (21.9 m to 27.4 m) gravel bottom is to be preferred, and furnishes just as good shelter in southerly and easterly weather. The mean range of tide is about 2 feet (0.6 m).