436 



Dr. Tempest Anderson and Dr. J. S. Flett. 



On the windward side of St. Vincent so much material is being 

 swept into the sea by the streams that the coast is covered with black 

 sand, and near Overland Village it is possible to walk for a mile 

 beneath the sea cliffs on a broad, sandy beach, where formerly the 

 heavy surf of a weather shore beat against their base. In the 

 arrowroot fields the original surface is often to a large extent un- 

 covered, and on the upper slopes of the Soufriere there are many 

 places where none of the new ash is left, but the bare surface of the 

 old rocks is everywhere exposed to view. After a heavy tropical 

 shower, valleys which are usually dry may be filled with a thundering 

 torrent several feet deep, and 20 or 30 feet across. Under these cir- 

 cumstances it will easily be understood that already many of £he 

 streams have thoroughly cleaned out the ash from the upper parts of 

 their channels where the gradient is steepest. 



But when such a torrent reaches the lower valleys, which have 

 been filled with thick masses of hot sand, a strange conflict between 

 fire and water can be witnessed. The river ploughs its way deeper 

 and deeper, constantly sweeping the material into the sea. The 

 valleys, at first almost obliterated, are now reassuming their old 

 appearance. Terraces on their sides give evidence of former levels at 

 which the streams flowed. There are five or six such terraces on the 

 Wallibu. This river flows in gushes of hot steaming black mud, its 

 intermittent flow being due to small land-slides temporarily damming 

 up its channel, only to be swept away as the pressure of the water 

 increases. On the Rabaca Dry River there has been less erosion, and 

 only after heavy rains does it reach the sea, as the water from the 

 smaller showers is apparently evaporated in its passage through the 

 banks of hot ashes. After rains, both rivers can be seen steaming all 

 along the lower parts of their courses. 



When one of these streams comes down in force it undermines its 

 banks by washing out the soft new ashes at their base. Then land- 

 slides take place, and a curious spectacle results. When the hot ash 

 tumbles down into the water, an immense cloud of steam rises in the 

 air to heights of hundreds of feet. It expands in great globular 

 masses exactly like the steam explosions from a crater, and as it drifts 

 away before the wind fine dust rains from the cloud. We had the 

 good fortune to witness a magnificent series of these explosions, one 

 day as we were descending from the summit of the Soufriere. It was in 

 the valley of the Rozeau Dry River. After every land-slip a column 

 of muddy Avater rose to about 200 feet carrying with it pieces of stone. 

 Immense quantities of steam shot up to 7 00 or 800 feet in the air. It 

 resembled an enormous geyser of black mud and steam. In the 

 Wallibu River, after every shower, these steam explosions may be 

 witnessed taking place on a large scale. After a few hours of dry 

 weather they cease, though the river can still be seen to be steaming 

 strongly as it flows along. 



