EROSION ON SAINT VINCENT AND MARTINIQUE 561 



The vast amount of material carried down by mud flows in the great gorges of 

 the Precheur, the Blanche, the Seche, the Des Peres, and the Roxelane rivers on 

 "the west and southwest sides of mont Pele was likewise lost in the depths of the 

 Caribbean sea without materially affecting the coastline. 



On the east side (the windward side) of both islands the shallow waters and the 

 prevailing currents deposited along the beach much of the new ash brought down 

 from the hillsides. The shoreline of Saint Vincent was pushed out from a few 

 yards to 50 or 60 yards for about 7 miles along the eastern coast of the northern 

 half of the island. Along the northern and northeastern coasts of Martinique 

 the effect was even more pronounced, because the mud flows or avalanches there 

 seem to have been more numerous. The extension of the shoreline was greatest 

 at the mouths of the Capot, the Basse Pointe, the Macouba, and the Grand rivers, 

 where it amounted at first to 100 to 200 yards. 



The erosive or abrasive work of the volcanic debris transported in the tornadic 

 blasts from the crater was shown on exposed opposing surfaces. Bluffs of this 

 character are more numerous on mont Pele, and the grooving due to this action 

 were observed along the Des Peres and Seche rivers and upon Morne Saint Martin, 

 a radial ridge beside the Riviere Blanche, directly in front of the great V-shaped 

 gash in the crater. On the Soufriere some overturned trees were noted, the roots 

 of which were turned toward the crater. These roots were charred and carved by 

 the volcanic sand blast on the sides toward the crater, while the bark on the sides 

 away from the crater was left fresh and uninjured. 



GRANDE SOUFRIERE OF GUADELOUPE 

 BY EDMUND OTIS HOVEY 



The field evidence indicates that the present active cone of this volcano is closely 

 analogous to the new cone and spine of mont Pele, Martinique — that is to say, it 

 has been pushed up bodily as a rigid mass into its present position or has welled 

 up through the conduit of the volcano in such a viscous condition that contact with 

 the atmosphere rendered it too rigid to form a flow, probably the latter. 



At the base of the cone, on the north, there is a gently rising plateau, apparently 

 a segment of a circle, which indicates the position of a part of the rim of a crater in 

 existence before the construction of the present cone. The remainder of the old 

 crater rim, if such this was, has been entirely covered by the present cone. The 

 top of the cone shows several jagged masses of solid lava rising to heights of 40 to 

 100 feet above the general level. There is no true crater or anything resembling 

 a crater in the cone. The cone, however, is traversed by a system of clefts or As- 

 sures, which are best developed along two main directions, crossing at an oblique 

 angle like a gigantic letter "X." The present vents of steam and sulphurous gases 

 lie in the great fissures, with the exception of the vent known as " Napoleon," 

 which is about 75 feet from one of the large fissures in a minor transverse fissure. 



From the sea the profile of the mountain leads one to infer that the present 

 active cone lies within a ruined crater 2\ miles or more in diameter. From the 

 summit of the mountain, however, this impression is dissipated by the relations 

 of the surrounding peaks and the peculiarities of the erosion forms, and the inde- 

 pendence of the Grande Soufriere as a volcanic center seems the more probable 

 view. 



