small heavy Bodies in Air, &c-. 25 1 



dilating successively portions of the atmosphere exposed 

 thereto in the directions of from east to west, produces, as is 

 well known, the trade winds of constant course in the same 

 direction. These efFects are principally produced at the surface 

 where the heat is greatest by accumulation. In the evenings I 

 have seen from the high lands of Barbados, the clouds and 

 lowermost scud transported by the regular lower current of 

 trade wind to distances to the westward of the island, meeting 

 there a contrary current of wind, and returning back by a slow 

 contrary course, at considerably increased altitudes over the 

 island, and over the loAver stratum of clouds. These changes 

 of the currents of air I had repeatedly observed. 



St. Vincent's is about seventy miles directly west from Bar 

 bados. In coming up from Martinique, I have been a week 

 in a small schooner between both islands without seeing either. 

 St. Vincents is generally not to be seen from Barbados ; and 

 yet, in a particular state of the atmosphere, I have, from the 

 heights of Barbados, seen distinctly St. Vincent's, the pitons 

 of St. Lucie, and the positions of Grenada and of Martinique, 

 from the collections of vapours which then gather around, and 

 hang over the tops of these and all the islands. In the night 

 preceding the firgt of May, 1812, the inhabitants and the gar- 

 rison of Barbados were alarmed by the noise of explosions from 

 the westward, which seemed to proceed from fleets engaged at 

 sea in that direction. At two or three in the morning, there 

 was a strange sort of dust dropping from the air, which 

 increased as the morning advanced. When day-light ap- 

 peared, a large body of vapour appeared to the northward of 

 east, slowing advancing over the island, producing, in a man- 

 ner sufficiently obvious, a darkness in the quarter from which 

 it came, carrying before it a bright portion of the sky bounded 

 by an apparently circular line of dimensions successively 

 diminishing until entirely shut in, and complete darkness 

 covered all things. 



The ordinary darkness of night, always illuminated more 

 or less by star-light, was not to be compared to this. It 

 was total and absolute. The eye could not sec the hand. 



