HISTORY OF MAURITIUS. 
183 
which rise to upwards of fifteen hundred fathom. The two islands, which are more 
than thirty-five leagues distant from each other, were, without doubt, formerly united, 
but have been divided by some violent effort of nature: there is indeed every 
reason to believe that they are still connected, though the conjoining parts are 
covered by the sea, and that some subterraneous passage forms a communication 
between them. 
“ The earthquake which happened in the Isle of France on the 4th of August, 
1786, appeared to favour this conjecture. On that day, at thirty-five minutes past 
six in the morning, a calm succeeded to a strong east and east-south-east wind, which 
had prevailed during four days; a subterraneous noise, that terminated by a sudden 
explosion, like the discharge of a cannon, was heard in the south-east quarter, and 
at the same moment two violent shocks were felt, the one vertical, and the other 
horizontal: the barometer did not on this occasion indicate the least change in 
the atmosphere, and an east-south-east breeze commenced within a quarter of an 
hour, and continued till eleven on the following night. This strange phsenomenon, 
was not accompanied with any destructive circumstance in the Isle of France; but 
it appeared that, at the same moment, the volcano in the Isle of Bourbon had 
poured forth a greater quantity of lava than it had done on the preceding days. 
“ It is reasonable therefore to suppose, that the combustible matter in the Isle 
of France had fermented till it took fire, and having met with a resistance superior 
to its own force, occasioned the shocks which have been mentioned; when, being 
impelled in every direction, it found a passage, by a subterraneous gallery, to the 
Isle of Bourbon, and not meeting with any resistance, issued from the crater of the 
volcano.” 
The succeeding Observation$ will enable our Readers to compare the Volcano of 
the Isle of Bourbon, with the two most celebrated Volcanoes of Europe. 
Mount Vesuvius is two leagues to the east of Naples, and about two thousand 
fathom from the sea; the circumference of its base is about ten leagues, and its ele¬ 
vation above the level of the sea, or the Gulf of Naples, is five hundred and ninety- 
five fathom. It divides at about two-thirds of its height, and its two summits are 
about five hundred fathom from each other; that towards the sea forms the volcano. 
Its first eruption, as recorded in history, was during the reign of Titus, in the 
seventy-ninth year of the Christian era, and which was rendered remarkable by the 
