HISTORY OF MAURITIUS. 
90 
they occupy; and then a passage is practicable over many parts of them. Nothing 
can be more agreeable than the parties of pleasure among them, when the sea is 
tranquil, and the weather is fine; as they represent a forest of coral of all colours, 
whose stems appear above the water. At the same time the polypi are seen to 
come from their cells in the form of plumes, and various fish of the most beautiful 
colours also present themselves to the view: the bottom is likewise decorated with 
oursins * of different kinds and hues;, though they are found in still greater numbers 
in the recesses of the coral. 
After gales of wind and hurricanes, the shores are strewed with the remains of 
the madrepores ,t filled with these oursins, and an infinity of fragments of other 
kinds; and the sea rises in such a manner, and so suddenly, on the edge of these 
reefs, that vessels may range along them to get into port. 
The reefs are nothing more than coral, or madreporse, worked in the sea by the 
polypi, and form a considerable steep or perpendicular bank, which is continually 
augmenting, either by the labour of those animals, or the power of the sea, which, 
in its boisterous state, covers it with fragments of the same substance, which it has 
broken off from their beds, or forced up from its own depths. The particular spots 
which the billows have reached during the hurricanes, are evident from the beds of 
fragments which the sea has left on withdrawing itself to its natural limits. Indeed, 
there is every reason to conclude, that hereafter a dry passage will be obtained to 
the very brink of the reefs of the Isle of France; as the foot of the island will be 
prolonged in such a manner, that the space now under water will become plains,, 
like those which have been already described. 
The Isles of Amber, to the windward of the Isle of France, are also a consider¬ 
able mass of coral, which the sea formerly cast up, and afterwards abandoned, as in 
the Isle of Tonneliers. There is no doubt but these islands and plains of coral 
rests on a base of vitrifiable sand and rock of quartz, which may be supposed to be 
a prolongation of the Isle of France; and that, from the inclination of its beds, it 
has proceeded, as well as the Isle of Bourbon, from the bottom of the sea. 
Luminous Globes , &c. 
Luminous globes are occasionally seen at Port Louis; which, being surrounded 
by very high mountains, that check the course of the winds, ire consequently 
* Echinus marinus. -Jr Coralla stellata. 
