THE SEYCHELLES 
203 
to the west of the Seychelles proper. They were not 
known in any detail until the renowned governor, Mahe 
de Labourdonnais, sent Capt. Picault to the Seychelles 
to take possession of them for the French. The prin¬ 
cipal island received the name of Mahe in his honour. 
From that time dates the first survey and exploration 
of the island, and shortly afterwards several Creole 
families emigrated from the Mascarenes to the Seychelles. 
The larger islands rise into considerable mountains, 
the highest of which is on Mahe and attains an 
elevation of 3240 ft., while Praslin reaches 3000 ft. and 
Silhouette 2444 ft. The primitive rock composing them 
is granite, which has the closest correspondence with 
that of Madagascar. The valleys are covered with a 
layer of fertile soil *, coral reefs exist almost everywhere 
in greater or less extent. Mahe is fringed by coral reefs 
on the east side, though there is proof that the area 
is one of elevation, as coral formations occur on the 
coast at 80 ft. above the sea. Praslin has reefs on the 
north and south-west sides, Curieuse on the north, while 
Silhouette seems to be entirely fringed with reefs. The 
Amirante Isles, according to Capt. Moresby, consist of 
coral and shell detritus, and project only some 60 ft. 
above the water. 
The climate is an excellent one according to A. Brauer, 
the heat being moderated by the trade wind, so that 
fevers are almost unknown; this is also indicated in the 
remarkable fact that the percentage of births among 
the inhabitants is largely in excess of that of deaths. 
The oscillations of temperature during the year are 
strikingly small, ranging only from 79° to 84° F. The 
average obscuration of the sky is 5-3, that in January 
is 6-1, in April and May 4^9 and 4*8. 
Formerly it passed as an established fact that whirl¬ 
winds do not reach the Seychelles; this is not quite 
accurate, though it is true that cyclones occur but seldom. 
