[ 676 ] 
Hence, we fee that an outrageous Hurricane may 
be cauled, by deftroying a fmall Proportion of the 
Elafticity of the Air of any Place, in refpeft to the 
Whole. No Wonder then that fuch violent Com- 
motions of the Air fhould produce Hurricanes and 
Thunder-Showers; cfpecially in the warmer Cli- 
mates; where both the fulphureous and watry Va- 
pours, being rais'd much higher* and in greater 
Plenty, caufe more violent Effects. 
Monfieur cte Buffon , in his Natural Hiftory and 
Theory of the Earth, mentions black dark Clouds 
in the Air near the tempeftuous Cape of Good Hope, 
and alfo in the Ocean of Guiney , which are called 
by the Sailors the Ox’s Eye which are often the 
Forerunners of terrible Storms and Hurricanes. 
Whence it is to be fufpe&ed, that they are large 
Collections of fulphureous Vapours; which, by de- 
ftroying fuddenly a great Quantity of the elaftic Air,, 
caufe the ambient Air to rufh with great Violence 
into that Vacuity, thereby producing Tempefts and 
Hurricanes. And off the Coaft of Guiney they have 
fometimes three or four of thefe Hurricanes in a 
Day ; the Forerunners of which are thefe black ful- 
phurcous Clouds, with a ferene clear Air, and calm 
Sea; which on a fudden turns tempeftuous, on the 
Explofion of thefe fulphureous Clouds. And in 
Jamaica they never have an Earthquake when there 
is a Wind to difperfe the fulphureous Vapours. 
In the like manner we find, in the late Earth- 
quakes at London , and in the Accounts of many 
other Earthquakes, that, before they happen, there 
is ufually a calm Air, with a black fulphureous 
Cloud : Which Cloud would probably be difperfed 
like 
