KABAKA RIVER VALLEY 425 



along the postroad. In June, 1908, the main channel, dry except during 

 floods, was beside the old Eabaka sugar and arrowroot mill, part of which 

 had been carried out to sea by the torrents. This channel was 2 or 3 

 meters deep and 60 meters across. A few meters seaward from the post- 

 road the new and old floodplains merged into one expanse 700 to 725 

 meters across, forming a new shoreline. 



The ash that was cast into the Eabaka by the eruptions was coarser in 

 grain and apparently more abundant in quantity than that which was 

 thrown into the Wallibu; hence the middle reaches of the former have 

 been much less thoroughly cleared out than those of the latter, but they 

 show a similar succession of terraces. There are no statistics giving the 

 comparative rainfall of the windward and the leeward sides of the island 

 or of the mountain, so that it is impossible to state accurately which val- 

 ley has had the more frequent showers or the greater amount of water to 

 effect the transportation of the material. The catchment basin of the 

 Eabaka, however, is greater than that of the Wallibu, and the windward 

 side of the Soufriere-Morne Garu region probably receives a heavier rain- 

 fall than the leeward; hence, other factors being equal, the Eabaka gorge 

 would have been reexcavated before the Wallibu, but the coarse gravel 

 filling the Eabaka gorge allowed freer circulation of water than was 

 possible in the fine sand and dust filling the Wallibu, and the larger, 

 heavier grains required a greater quantity of water or velocity of stream 

 to transport them. Furthermore, the clearing of the Eabaka was delayed 

 by the necessity of cutting the new gorge already mentioned, though the 

 excavation was carried on with great rapidity, once it was begun. 



Windward Shoreline 



Before the eruptions of 1902-1903 began the shoreline at the mouth of 

 the Eabaka was essentially straight, according to the admiralty chart, it 

 being evident that no more material was brought down by the floods of 

 each rainy season than could be distributed by the currents during the 

 succeeding dry months. The immense amount of debris brought down 

 during and after the recent eruptions extended the shoreline at the mouth 

 of the stream in a broad delta! fan some hundreds of meters into the sea, 

 but it is not possible to state just how far, since I neglected to make meas- 

 urements either in 1902 or 1903, and I have seen no mention of the 

 matter in others' reports. In 1908 I made some measurements by pacing, 

 and determined that the shoreline was still about 200 meters beyond the 

 old strand near the new mouth of the Eabaka, presenting to the sea a low 

 bluff 2 to 4 meters high, at the base of which was an apron, several meters 



XXXIX — Bull. Geol. Soc. Am., Vol. 20, 1908 



