306 DR. JOHN S. FLETT: PETROGRAPHICAL NOTES ON THE PRODUCTS OF 
The Ejecta of the Eruptions of May, 1902. 
Among the materials ejected during May, 1902, there were not only ashes and 
sand, with volcanic bombs which were derived from the active magma within the 
crater, but also large quantities of the older rocks of the mountain which had been 
torn from the walls of the crater and were mingled with the new ashes. The 
difficulties of collecting from the deposits of hot sand laid down by the avalanche 
were considerable, as the principal stream sections of the new materials were too hot 
and too unstable to be approached. Fragments lying on the surface of the avalanche 
evidently belonged to the most recent stages of the volcanic activity. The deeper 
parts of the new deposit were usually inaccessible, but where the secondary steam 
explosions had built small cones on the rivulets it was easy to collect blocks that had 
been projected from the interior of the beds of hot ash. These form the major part 
of the ejected blocks of 1902 contained in our collections. 
The ashes and sand gathered in Barbados, Kingstown, Chateaubelair, and other 
localities during May, 1902, and at subsequent times can, of course, be assigned at 
once to their respective eruptions, and, with the large semi-vitreous bombs scattered 
over the surface of cultivated grounds on both the windward and leeward sides of the 
island, may be taken as satisfactory evidence of the nature of the new magma within 
the crater. It seems clear, however, that some of the previous eruptions produced 
bombs not essentially differing from those of 1902, and these can only be distinguished 
by the traces of decomposition they sometimes show, or by the positions in which 
they are found. 
Volcanic Sand and Dust. 
As stated in the first part of this report, fine sand and dust formed the greater 
part of the hot avalanche, and were the only materials transported to a considerable 
distance. The Barbados dust has been described by several writers,* and is now well 
known to most of those who are interested in volcanoes. We have also examined 
specimens from Kingstown, Calliaqua, and other localities in the south part of 
St. Vincent, and from Wallibu, Georgetown, and the southern flanks of the Soufriere. 
These have a great similarity in general character, though they may not be of 
* Flett, John S., “Note on a Preliminary Examination of the Dust that fell in Barbados after the 
Eruption in St. Vincent” ‘Quart. Jour. Geol. Soc.,’ vol. 58, p. 368 (1902). Falconer, John D., 
“Volcanic Dust from the West Indies,” ‘Nature,’ vol. 66, p. 132 (1902). Porter, T. C., “Volcanic Dust 
from the West Indies,” ‘Nature,’ vol. 66, p. 131 (1902). Klein, C., “Ueber die am 7. Mai 1902 vom 
Vulkan Soufriere auf St. Vincent ausgeworfene vulkanische Asche,” ‘Sitzb. Berlin. Akad.,’ 1902, p. 992. 
Diller, J. S., “Volcanic Rocks of Martinique and St. Vincent,” ‘National Geographic Magazine,’ 
vol. XIII., p. 285 (1902). Smith, Longfield, “Volcanic Eruptions in the West Indies,” ‘West Indian 
Bulletin,’ vol. III., p. 271 (1902). 
