National Geographic : 1902 Dec
THE ERUPTIONS OF LA SOUFRIERE, ST VINCENT, IN MAY, 1902 By EDMUND OTIS HOVEY HE surface rocks of the island of St Vincent are wholly of direct volcanic origin, with the excep tion of some elevated beach conglom erates occurring along the windward (eastern) coast. These conglomerates, too, are composed of boulders and gravel of volcanic origin derived from the island itself. These conglomerates, water-worn sea benches at three alti tudes, elevated sea caves, and the evi dence of an old shore line northwest of Georgetown are indications of an eleva tion of the island of about 200 feet during recent geologic time. The south ern portion of the island is the oldest, as is evidenced by its stage of erosion, which is much farther advanced than that of the northern part. Broad val leys, with bottoms of comparatively gentle slope, are to be found about Kingstown, Calliaqua, Mariaqua, Meso potamia, and elsewhere in the south, while the northern half of the island is remarkable for the extremely rugged character of its topography. Volcanic activity on St Vincent has moved from south to north, as it has on Martinique, St Kitts, and some of the other Caribbean Islands, but it has long centered about the present active crater, La Soufriere. Numerous lava beds al ternate with the, apparently, far more extensive beds of tuff agglomerate in the make-up of the island. Tremen dous eruptions of the explosive kind, like the present one, though on a far larger scale, have been frequent occur rences in the geologic history of the island. According to Hill,-j - the vol canic Caribbean Islands date from at least as far back as Eocene time, but eruptions have been very rare within historic time, which extends over four centuries. The heaviest recorded erup tions have been those of La Soufriere, which took place in 1718 and in May, 1812. The latter is said to have formed the ' New ' crater, 500 feet in diam eter, on the northeast side of and higher than the much larger " Old" crater. The Old crater was about nine tenths of a mile long from east to west and about eight-tenths of a mile wide from north to south, according to the British Admiralty chart, and was famous * The author was sent to Martinique and St Vincent by the trustees of the American Museum of Natural History, New York, as the representative of that institution, to study the phenomena in connection with the eruptions of the present year. I was a passenger with the delegates of the National Geographic Society on the United States cruiser Dixie on her memo rable voyage for the relief of the impoverished inhabitants of the devastated islands, and I indorse most heartily the praise given by I. C. Russell and R. T. Hill, in their reports to the Society, to Capt. R. M . Berry, U. S. N ., commanding the Dixie, and to the other officers of the cruiser for their hospitality and their kindness to the scientists. On St Vincent our work was greatly facilitated by the intelligent activity of F. W . Griffith, government clerk, acting under general instructions from Sir Robert Llewellyn, C. M. G , gov ernor of the colony, and by the assistance rendered by T MacGregor MacDonald, a planter owning several estates on the leeward (west) side of the island. James E. Richards, a merchant of Kingstown, placed at the disposal of my colleagues (Dr. T . A. Jaggar, Jr., and George Carroll Curtis) and myself his cottage at Petit Bordel, near Chateaubelair on the leeward coast, from which there was an unobstructed view of the volcano. The facts embraced within this article have been embodied, together with the author's observations on Mont Pelee, in a " Preliminary Report," presented to the trustees of the American Museum of Natural History, and published in the " Bulletin " of the Museum, vol. xvi, pp. 333-372, pls. xxxiii-li . j This Magazine, vol. xiii, p. 229, July, 1902.