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in the western and south-western portion of the horizon. 

 These became denser as they approached, until they formed 

 a mass of an ash-grey colour, projected on a sky of a paler 

 tint, while the rugged outliers from the mass, of the peculiar 

 form which indicates a high degree of electrical tension, showed 

 plainly that a storm was approaching. About half-past three 

 o'clock it burst forth. The flashes of lightning (generally 

 forked) succeeded one another with rapidity, and at length 

 the roar of the thunder seemed continuous. Some persons who 

 observed the phenomena from a distance were able to distin- 

 guish the two strata of oppositely electrical clouds, and to see 

 the electrical discharges passing between them. 



" Hitherto the wind was light, and there was that peculiar 

 closeness in the air which is the result of high temperature and 

 excessive humidity. Shortly before four o'clock the rain com- 

 menced ; this was followed almost immediately by discharges 

 of hail, and at four, p. m., the terrific tornado, which was the 

 grand and peculiar feature of this storm, reached us. 



" This gale, which appears to have been a true whirlwind, 

 first sprung up from the south-east, driving the hail before it 

 impetuously. It then suddenly, and apparently in an instant, 

 shifted to the point of the compass diametrically opposite, and 

 blew with increased violence from the north-west. The noise 

 about this time of the shifting of the wind was terrific, and 

 arose (as is conjectured respecting similar tropical phenomena) 

 from the confused conflict of hail in the air. The size of the 

 hailstones, as well as the vehemence of the gale, appeared to 

 be greater during the second phase of the storm than the first. 

 These masses, many of which were as large as a pigeon's egg, 

 were formed of a nucleus of snow or sleet, surrounded by 

 transparent ice, and this again was succeeded by an opaque 

 white layer, followed by a second coating of ice. In some of 

 them I counted five alternations. 



" In less than ten minutes the tornado had passed. The 

 wind returned to a gentle breeze from the south-west, the 



