UNITED STATES COAST PILOT.

HAWAIIAN ISLANDS, INCLUDING THE ISLANDS, ROCKS, AND SHOALS WESTWARD.

GENERAL INFORMATION.

This volume contains information regarding the islands of Hawaii, Maui, Kahoolawe, Lanai, Molokai, Oahu, Kauai, Niihau, and the adjacent small islands, and includes the islands and reefs extending in a west-northwesterly direction to Midway and Ocean Islands.

The Hawaiian Islands are situated near the northern limits of the Tropics, the larger ones lying between 18° 55′ and 22° 15' north latitude, and between 154° 50' and 160° 30' west longitude. The islands are of volcanic origin, and it is said that their formation occurred at various periods, those at the westerly end of the group being the oldest and those at the easterly the youngest. This difference in the age of the islands accounts for the difference in appearance as viewed from offshore. Hawaii, the youngest island of the group, shows very little evidence, comparatively speaking, of erosion, while Kauai, the oldest of the larger islands, is considerably cut up by gorges and ravines. On almost all of the islands the northeasterly slopes are the most irregular, as the rainfall generally is the greatest on this side, resulting in torrents that cut ravines in the slopes of the islands. The 20-fathom curve rarely extends over 1 mile from shore and usually is only a short distance beyond the coral reef which in some places fringes the coast line of the islands. There are few off-lying dangers, and usually these are indicated by breakers or by a change in the color of the water.

STREAMS.-There are numerous streams, nearly all of which may be classed as mountain torrents, although a few are navigable for small boats. The streams are usually found on the north and east

coasts.

CLIMATE. Owing to the location of the islands, the climate is equable, the mean monthly temperature at Honolulu varying from 70°.7 in February to 78°.1 in August. (See table on page 89, giving average conditions at Honolulu.)

WINDS.-The northeast trade winds prevail throughout the year. During the summer months they are almost continuous and usually veer a little to the north of the average direction. During the winter months they are apt to be interrupted by variable winds, or by "konas," the local name for strong southerly or southwesterly winds, which sometimes occur. The trades veer more to the easterly in the winter. The konas, which occasionally occur between October and April, last from a few hours to two or three days and are attended by rain. During the konas all anchorages on the lee side of the islands are unsafe.

NOTE.-Instructions regarding "Navigational aids and the use of charts" and other useful data are contained in an appendix beginning at page 62.

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While the trade winds are blowing, frequent calms and light variable winds may be found for several miles to leeward of the larger islands. Along the west coast of Hawaii and the south coast of Maui the land and sea breezes are very regular, the wind blowing onshore during the day and offshore at night. In general, fair weather may be expected from May to October.

RAINFALL. The rainfall in the Hawaiian Islands varies greatly in the different localities and is influenced by the location with respect to winds and mountains. The greatest rainfall is usually found on the windward side of the islands. In general, the winter is the rainy season, although there is no month without some rain. From observations made at different stations it is found that the amount of rainfall often varies greatly at the same station for the same months in different years or for the total rainfall of different years.

FOG does not occur around the islands, and except for rain squalls, mist, and haze, there is no thick weather. The mountains on the islands, however, are often obscured by clouds.

STORM WARNINGS.-No storm warnings are displayed in the Hawaiian Islands, but special forecasts are made from the Weather Bureau station at Honolulu. Mariners and others may have their barometers compared with standards at that station, which is located in the Alexander Young Building.

NAVIGATION LAWS of the United States are published by the Bureau of Navigation, Department of Commerce, at intervals of four years, the present edition being that of 1919. This volume can be obtained from the Superintendent of Documents, Government Printing Office, Washington, D. C., at a price of $1.

TIDES.-The periodic tides in this locality are usually small, the average rise and fall being from 1 to 2 feet. The high water intervals vary from 2 to 334 hours, and, in general, the tides occur from about an hour to an hour and a half earlier along the northern coasts than they do along the southern coasts of the islands. The Tide Tables, which are published annually in advance by the Coast and Geodetic Survey, contain the predicted tides for each day in the year for Honolulu and also tidal differences for a number of other places in the Hawaiian islands.

CURRENTS.-The currents are, as a rule, greatly influenced by the direction and strength of the trade winds. In general, there is a westerly set due to the prevailing northeasterly trade winds, but they are subject to considerable variations both in force and direction at different seasons. The tidal currents seem to have but little influence and are not generally taken into consideration.

POPULATION.-By the census of 1920 the islands had a population of 255,912.

PRODUCTS.-Agriculture is the principal occupation of the inhabitants. The principal products are sugar, pineapples, coffee, and cattle. Tropical fruits and vegetables are also cultivated. Sheep and hogs are raised to some extent.

TRADE. The principal trade is with the United States. The port of entry is Honolulu. The subports are Hilo and Mahukona, Hawaii; Kahului, Maui; and Koloa, Kauai. The custom station for Koloa is at Eleele, locally known as Port Allen.

STANDARD TIME. The standard time of the Hawaiian islands is 157° 30' west longitude time.

COMMUNICATION with San Francisco, Vancouver, Auckland, Sydney, Manila, Yokohama, and Hongkong may be had by several regular lines of steamers which touch at Honolulu. There is also a line of steamers to Seattle and Tacoma and another to the Isthmus of Tehuantepec via San Francisco. There is frequent communication by interisland vessels around the islands.

RAILROADS.-A railroad skirts the shores of Oahu westward from Honolulu along the southwesterly and northwesterly sides and halfway down the northeasterly side. Another extends northwestward from Honolulu about one-half the way across the island. Railroads extend northwestward, southward, and southeastward from Hilo. Railroads also extend a short distance northeastward, southward, and northwestward from Kahului. There are other short railroad lines at various places.

HIGHWAYS.-There are good highways in many parts of the islands, and carriages or automobiles can be obtained at most of the towns. CABLE. There is communication by cable to San Francisco and to Manila via Midway and Guam. There is good telephone service on all the large islands.

WIRELESS TELEGRAPH.- There is wireless telegraph communication between the islands and with the United States and the Orient. QUARANTINE.-National quarantine laws are enforced in the islands by officers of the United States Public Health Service.

MARINE HOSPITAL.-There is a relief station of Class II of the United States Public Health Service at Honolulu. The office is in the customhouse.

ANCHORAGES are numerous, except on the northerly and easterly sides of the islands, the first requirement under ordinary conditions being shelter from the trade winds. During kona weather most of the anchorages on the southerly and westerly sides of the islands are unsafe.

AIDS TO NAVIGATION.—The lighthouses and other aids to navigation are the principal guides and mark the approach and channels to the important ports. The buoyage accords with the system adopted in United States waters. For a description of all aids see the Buoy List, Hawaiian and Samoan Islands, published by the Lighthouse Service, which can be obtained from the Superintendent of Documents, Washington, D. C., price 20 cents, or from the agents listed in the weekly Notice to Mariners.

SYSTEM OF BUOYAGE. In conformity with section 4678 of the Revised Statutes of the United States the following order is observed in coloring and numbering buoys in United States waters, viz: In approaching the channel, etc., from seaward, red buoys, with even numbers, will be found on the starboard side. In approaching the channel, etc., from seaward, black buoys, with odd numbers, will be found on the port side. Buoys painted with red and black horizontal stripes will be found on obstructions, with channel ways on either side of them, and may be left on either hand in passing in. Buoys painted with white and black perpendicular stripes will be found in mid-channel and must be passed close-to to avoid danger. All other distinguishing marks to buoys will be in addition to the foregoing and may be employed to mark particular spots. Perches, with balls, cages, etc., will, when placed on buoys, be at turning points, the color and number indicating on what side they shall be passed.

Nun buoys, properly colored and numbered, are usually placed on the starboard side and can buoys on the port side of channels. Day beacons (except such as are on the sides of channels, which will be colored like buoys) are constructed and distinguished with special reference to each locality and particularly in regard to the background upon which they are projected. Dredging buoys are white, with the tops for a distance of 2 feet painted green.

PILOTAGE is compulsory for certain vessels. There are pilots at the principal ports who come off in small boats to vessels making signal outside the entrance.

HARBOR CONTROL.-A harbor master is appointed for each of the harbors of Honolulu, Hilo, and Kahului, and they have charge of the anchorage and berthing of vessels in their respective harbors. For harbor regulations see Appendix.

TOWBOATS.-There are no seagoing towboats in the islands. The local steamers do towing. In some of the harbors there are large launches which sometimes assist lighters and vessels when inside.

SUPPLIES.-Provisions, ice, lumber, and some ship-chandler's stores can be obtained at Honolulu, Hilo, and Kahului. Some provisions can be obtained at other places.

WATER can be conveniently obtained at Honolulu, Hilo, and Kahului. Water can be obtained also from streams at many places. FUEL. Coal and fuel oil (for vessels) can be obtained at Honolulu, Hilo, and Kahului.

REPAIRS.-There are machine shops at Honolulu, Hilo, and Kahului, and ordinary repairs to machinery can be made. There is a floating dry dock at Honolulu with a dead-weight capacity of 4,500

tons.

WHARVES AND LIGHTERS. -At several of the ports there are wharves at which vessels can lie to discharge and load, but at all others vessels discharge or load either by lighters or wire cable.

RADIO SERVICE.

TIME SIGNALS.-In connection with the service over the land telegraph lines, time signals by radio are sent daily, Sundays and holidays excepted, from certain United States naval coastwise radio stations on the Pacific coast and at Honolulu, as follows:

The signals begin at 5 minutes before the hour and continue for 5 minutes. During this interval every tick of the clock is transmitted except the twenty-ninth second of each minute, the last 5 seconds of each of the first 4 minutes, and finally the last 10 seconds of the last minute. The final signal is a longer contact after this long break. Hydrographic information, weather reports, and other information of benefit to shipping are sent out from these stations.

The supervision of radio communication in the United States, including the Hawaiian Islands, is controlled by the Bureau of Navigation, Department of Commerce. A list of the radio stations of the United States, including shore stations, merchant vessels, and Government vessels; Radio Communication Laws and Regulations of the United States; and Amateur Radio Stations of the United States are published by that bureau. Any of these publications can be obtained from the Superintendent of Documents, Government Printing Office, Washington, D. C.; price, 15 cents each. Changes or additions to the stations and to the laws and regulations are published in bulletins issued monthly; price, 5 cents per copy or 25 cents per year.

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The International List of Radio Stations of the World (edition in English) can be procured from the International Bureau of the Telegraphic Union (Radiotelegraphic Service), Berne, Switzerland. addition to the information contained in the list of the United States stations published by the Bureau of Navigation, the international list shows geographical locations, normal ranges in nautical miles, radio systems, and rates. Supplements to the international list will be issued monthly and will contain new stations and tables of alterations. Inquiries as to the subscription prices of these lists should be made direct to the Berne bureau at the address given above. Remittances to Berne should be made by international postal money orders.

RADIO COMPASS BEARINGS.-The Naval Communication Service will furnish radio bearings to mariners of all vessels equipped with radiotelegraph transmitters. While the use of these bearings should not lead a mariner to neglect other precautions, such as the use of the lead, etc., during a fog, these bearings will greatly reduce the dangers to navigation for mariners who are compelled for any reason to proceed during foggy or misty weather.

These radio compass stations are provided, primarily, to assist the mariner in closing the land during fog or poor visibility, but they may also be used to obtain the positions of vessels at sea in radio compass range, about 150 miles, when for any reason positions can not be obtained by other means. The maximum distance for which bearings from these stations are accurate is 150 miles. But accurate positions can not be plotted when more than 50 miles from the shorė on Mercator charts, for the Mercator projection introduces a distortion of the true bearing.

For plotting radio compass bearings the U. S. Coast and Geodetic Survey publishes three plotting charts, which may be obtained by application to the Director, Coast and Geodetic Survey, Washington, D. C., or the sales agents, price 20 cents each. Full directions for using them are printed on the reverse side of each chart.

Radio compass stations are divided into two classes: (a) Single stations, operating independently and furnishing a single bearing. These stations are located with the view of giving service to ships at a distance of not over 150 miles from the station. (b) Harbor entrance groups. All stations in harbor entrance groups are connected to and controlled by the master station. All stations of the group take bearings simultaneously and these bearings are transmitted to the ship requesting them by the control station. The purpose of