The New International Encyclopædia/Luzon

LUZON′, Sp. pron. lo͞o-thō̇n′. The most important, and with the exception of a few islets the most northern, of the Philippine Islands.

Location and Boundaries. Luzon is situated between latitudes 12° 32′ and 18° 39′ N., and between longitudes 119° 42′ and 124° 8′ E. Its northern extremity, Punta Mayraira, is 217 miles due south of Formosa, and 520 miles southeast of Hong Kong. The Pacific Ocean proper and the China Sea meet on its northern coast. The southern coast is washed by a number of channels and seas separating Luzon from the rest of the archipelago, the chief of these being the Strait of San Bernardino, 10½ miles wide, between Luzon and the island of Samar on the southeast, and the channel, 7½ miles wide, separating Mindoro from the southwest coast.

Area and Configuration. The area of Luzon has been variously estimated at from 37,000 to 47,000 square miles. The official estimate of 1902 is probably the most nearly correct, and gives 43,075 square miles for the mainland and 1160 for the 311 small dependent islands, giving a total of 44,235 square miles, which is nearly the total for the State of Pennsylvania. Its area is according to this estimate somewhat less than that of Mindanao (q.v.). The shape of the island is extremely irregular. It may be divided into three parts, connected by narrow isthmuses: Northern Luzon, the main body, with a length from north to south of 270 miles and a width of 130 to 140 miles; Central Luzon, 56 by 90 miles, connected with the first by two isthmuses, one on each side of the Laguna de Bay; and Southern Luzon, a long, narrow, and irregular body stretching 160 miles to the southeast. The coast is very much indented, with numerous large bays, some of which form excellent harbors. The chief bays are, on the west coast, the Gulf of Lingayén and Manila Bay; on the south coast, the bays of Tayabas and Ragay, and the port of Sorsogón; and on the east coast, the bays of Albay, Lagonoy, San Miguel, and Lamón.

The principal dependent islands belonging to Luzon are, with their areas in square miles, the Batanes (81) and the Babuyanes (179), two groups of small islands lying north of Luzon, the former being the extreme northern group of the archipelago; Polillo Island (203), near the centre of the eastern coast; Alabat (60), at the mouth of the Bay of Lamón; Catanduanes (704), off the southeast coast; and a number of smaller groups and islets, chiefly off the east coast.

Geology and Topography. Our knowledge of the geological structure of Luzon is meagre, owing to the natural difficulty arising from the dense vegetation, which leaves the rocks exposed in very few places. The geological formations, however, include the following: Gneiss and diabasic rocks, Eocene limestone, conglomerates, sandstones, recent formations containing marine fossils, banks of coral limestone, and recent volcanic rocks. Extensive inland beaches containing fossils of existing marine species indicate a recent upheaval, and Southern Luzon was probably at no very distant period a separate island.

The mountains of Luzon are included in three principal ranges, which unite in a common nucleus at Mount Caraballo Sur on the northern boundary of the Province of Nueva Ecija in North Luzon. The Sierra Madre range stretches in a continuous chain along the eastern coast, terminating in Cape Engaño, the extreme northeastern point of the island. The Central and North Cordilleras run in a more broken chain parallel with the western coast, and with the Sierra Madre inclose the large basin of the Rio Grande de Cagayán. The third great system runs southward along the eastern coast and occupies the whole of South Luzon, terminating in Point Sual at the extreme southeastern end. The principal detached chain is the Cordillera de Cabusilán, running along the western coast from Manila Bay to the Gulf of Lingayén, inclosing between it and the eastern chain the large central basin of the Agno and Pampanga rivers. The average height of these ranges is from 2000 to 4000 feet. Mount Datá of the Central Cordillera rising to a height of 7364 feet, the highest point in Luzon next to the isolated volcano Mayón, which reaches a height of 7566 feet.

There seem to be two distinct lines of volcanic activity in Luzon, the eastern line containing the active volcanoes of Bulsan, Bacon, and Mayon in the southeastern part. Cana at the northeastern extremity, and the extinct Isaróg north of Mayón; the western line contains the active volcano of Taál in West Central Luzon, and the extinct peaks of Aráyat and Súngay. Mayón is the most active, and has in the past century emitted considerable quantities of lava, but all of them seem now to be in the last stages of activity. Earthquakes are of frequent occurrence, and have on several occasions caused great losses of life and property, notably in 1863, when large parts of Manila were laid in ruins, and in 1880, when the whole island was convulsed with a series of severe shocks. The style of architecture has to be adapted to withstand these disturbances.

Hydrography. Luzon, like all of the East India islands, is exceedingly well watered. The largest river system of the island, as well as of the whole archipelago, is that of the Rio Grande de Cagayán, running north from Caraballo Sur, which is the principal watershed for the three largest rivers of the island, the other two being the Pampanga, running south into Manila Bay, and the Agno, flowing west into the Gulf of Lingayén. The Abra and the Pagsáu in the northwestern part are also considerable, and besides these there are numberless short streams running down from the Cordilleras on all sides. Luzon has two large and several smaller lakes. The largest is the Laguna de Bay, separating Central from North Luzon, and communicating with Manila Bay through the Pasig River. The other large lake is Taál, lying southwest of the former, and containing the island volcano of the same name. In the wet season several of the rivers expand into temporary lagoons, the plain of Candaba, east of the Pampanga River, being periodically a lake 24 miles in extent.

Climate (for a general description, see Philippine Islands). Owing to its higher latitude and to the fact that it is more exposed to the various winds, Luzon enjoys a climate somewhat cooler, less equable, though more agreeable, than that of the southern islands. The annual rainfall, though considerable (amounting at Manila to 75 and even 120 inches), is less than that of the other islands. Luzon lies directly in the path of the typhoons, known locally as baguios, which sometimes work considerable damage to property on shore as well as to shipping. Violent thunderstorms are also frequent.

Flora and Fauna. These do not differ materially from those of the other islands, and are described in the article Philippine Islands (q.v.). Vegetation is everywhere extremely luxuriant, and large areas are covered with valuable forests.

For history, see Philippine Islands.

COPYRIGHT, 1903, BY DODD, MEAD & COMPANY.