326 E. 0. Hovey— Eruptions of 1902 of La Soifriere, 



a great outburst from the crater just in advance of the flood in 

 the Dry River Yallej. 



It is evident that there was a blast or a series of blasts of 

 hurricane violence from the crater of the Soufriere as well as 

 from that of Mt. Pelee, as a feature of the eru}3tions of 1902. 

 The effects were not so appalling, however, on St. Yincent as 

 on Martinique, because no large city was destroyed there. 

 The overturned trees constitute the principal evidence on the 

 island of St. Vincent. They all point away from the crater, 

 except for slight modifications due to local topography (see 

 ^g. 10). The blast extended radially in all directi(>ns from 

 the crater, suggesting the explanation that some great vol- 

 ume of steam, rising from the throat of the volcano, could 

 not find room for expansion upward, on account of the column 

 of steam and ashes which had preceded it, and the ashes fall- 

 ing therefrom, and that it expanded with explosive violence 

 horizontally and downward, following the configuration of the 

 mountain. This accords with the testimony of Mr. MacDonald 

 and other eye-witnesses of the eruptions, who say that they 

 saw the clouds of " smoke " (dust-laden steam) rushing down 

 the sides of the mountain with terrific speed. This dust-laden 

 steam was able to do much work of erosion, as is shown by 

 the horizontally scoured sides of some of the exposed cliffs and 

 by the trunks and roots of trees. The roots particularly have 

 been charred by the heat and have been carved into fantastic, 

 pointed shapes, as if they had been subjected to the action of a 

 powerful sand-blast. Erosion has not materially affected the 

 original surface of the ground as yet, because almost every- 

 where one can find the living roots and charred blades of 

 grass and other vegetation beneath the covering of dust and 

 lapilli, the first of which acted as a protection against the heat 

 of the rest, j^ow, however, the heavy rains take up vast 

 quantities of the loose lapilli for use as a powerful scouring 

 agent in attacking the denuded hillsides, and thus old valleys 

 are being deepened and widened. 



The particular feature of the May eruptions of the Soufriere 

 was the enormous amount of dust* which was thrown into the 

 air and distributed over a vast circle or ellipse the area of 

 which cannot yet be calculated for lack of data. The British 

 steamship Coya had an eighth of an inch of volcanic dust 



* The following chemical analysis is of dust from the May eruptions 

 which I collected May 27 in a room in the Langley Park estate house, about 

 one mile north of Georgetown, St. Vincent, in which twenty-one dead bodies 

 were found after the eruption of Ma}^ 7, The analysis was made by Dr. W. 

 F. Hillebrand of the United States Geological Survey, to whom my acknowl- 

 edgments are due, and is the unpublished analysis referred to in his article 

 in the National Geographic Magazine for July (vol, xiii, p. 297) as empha- 

 sizing the greater amount of sulphur present in the ejecta of La Soufriere 



