Red Sea.—Ancient chronicles report eruptions near Medina in the years 1254 and 1276 (Hum boldt, Kosmos, iv. 337). Von Hoff found porous lavas south of Mecca, in various places down to Hamar, in lat. 15° N. Jabl Tier (Bird Island), in the Red Sea. (lat. 16° N.), sends out vapour continually, and is composed of volcanic rock. In May 7th to llth, 1861, volcanic eruptions occurred at Edd, on the African coast of the Red Sea, in lat. 13° 57' N., and lon,g. 41° 4' E. Earth quake shocks on the 7th and 8th continued for an hour. At sunrise fine dust fell, at finst white, afterwards red ; the day was pitch dark, and tho dust was knee-deep. On the 9th the fall of ashes abated, and fire WM seen issuing from Jabl Dubbeh, mountain about a day's journey inland.
Aden promontory, just outside the Straits of Bab-ul-Mandab, is entirely volcanic. Tho town of Aden occupies the bottom of a well-defined breached crater a mile and a half in diameter en circled by precipitous walls from 1000 to 1f300 feet high, and backed by still higher masses of volcanic rock. Pumice is regularly mined for export. There is, however, no record of this crater being active.
Socotra, opposite Cape Guardaftli, leer a canic peak, called Jabl liajier, 5000 feet in height. .3./akran and Cutelt.—Proceeding eastwards, on the littoral of the Arabian Sea, hi Ilinglaj, or Makran, the ancient Gedrosia, aro series of loud volcanoes in continuoua action. They aro known to the Hindus as the Rama 'Chandra Kup, and aro visited by pilgrims, who regard as miraculous the periodical elevation of the semi-liquid maaa.
Crack is farther eastivards. In Juno 1810 it had a severe shock of an earthquake, by which some hundreds of the inhabitants perished. At sunset, the shock wins felt at Sindri ; its little brick fort was overwhelmed by a great wave, which converted a hard and dry tract into an inland lake, extending for 16 miles on each aide of Sinciri, while 5 miles north of that place there arose a mound of earth, about 10 feet high, ex tending nearly east and west about 16 miles, and crossing the Pharran river, which was cut off from entering the sea. The natives called the mound Allah Baud. A flood of the Narra of 1826 partially reopened it.
The Peninsula of India, in its central and western portion, between lat. 17° and 21° N., has been overflowed in prehistoric times by waves of basaltic lavas, which alternate with a fresh water deposit, usually calcareous. The basalt forms elevated plateaux of many miles in extent, and seems to have flowed horizontally, in repeated sheets, over the bottoms of shallow tertiary lakes ; but from what particular vents does not now appear, AS only one crater at the Lunar Lake has been traced. The basalt is often amygdaloidal,
contains much augite, and is occasionally nodal/it in structure rather than columnar. It has altered ninny of the sandy beds on which it reposes, or among -which its dykes have penetrated, into jasper and other metamorphic substances (Hislop and Hunter, Journ. Geol. Soc. xi. p.370). Farther south, on the eastern side of the Peninsula, in the Ongole, Guntur, and Nellore districts, and towards Madras, slight shocks of earthquakes repeatedly occur, and noises are heard there and in the Vinukonda taluk.
Coast of India.—Along the littoral of the Bay of Bengal, about 10 feet belew the surface am beds of tenacious black clay, embedded in Incas trine remains. In the year 1757, a volcanic island arose off Pondicherry, south of 3fadras, and, after remaining for severzd days above the water, throw ing out smoke and flame, it disappeared. About the same time, Cheduba (lat. 18° 40' N.) and the ialands along the shores of the Arakan coast were suddenly raised about 10 feet, having twice before, at intervals, as is suppoaed, of half a century, sustained similar upheavals. In 1762, during a violent e,arthquake, a mountain had sunk and dia appeared near Chittagong ; another had sunk down until the summit alone remained visible, and GO square miles of seit-shore were permanently submerged (Dr. Iluist, Bombay Geog. Soc. Journ. for 1856, p. 8). The island of Ramree (lat. 19° N.) is said to have been in liolent eruption in March 1839 ; and, on the 10th January 1869, districts a little farther northwards suffered greatly from an earthquake, of which Asoloo was the centre. Sand and hot water came up, forming cones in several places. cachar, IVongong, and places as far up into the Gangetic delta as Monghir, suffered a good deal.
Barren Island, in the Bay of Bengal, esatof the Andaman Isles, is a permanently active volcano, with a cone about 4000 ft high, rising in the centre of circular cliff-range which entirely surrounds. it except at one point, where the sea has broken in. The explosions of this volcano recur regularly a.t intervals of about ten minutes. North of this (lat. 13° 24' N.), the island of Narcondam has shown volcanic activity. It is a cone 700 feet high, with streams of lava visible on its flanks.