HISTORY OF MADAGASCAR. 
29 
many of the rivers are choked up with sand ? so that their 
waters either pass sluggishly into the sea, or, when not 
swollen by rains falling in the interior, present the aspect 
of a broad, unruffled, stagnant lake, for several miles inland. 
The brackishness of the water, and the absence of croco¬ 
diles, often indicate a level below that of the waters of the 
sea, while much of the ground on the inland side of the 
bank of sand that is raised along the border of the sea, 
being below the level of the ocean, extensive morasses 
occur in several parts of the coast. Many of the lakes are 
also shallow, and receive large quantities of vegetable mat¬ 
ter, furnished in all the rank luxuriance which the heat 
and humidity of the climate unite to produce; and some of 
these sheets of water, from the trees and shrubs that grow 
around, and rise in different parts of their surface, bear a 
greater resemblance to insulated forests than ordinary 
lakes. 
The effluvia arising from the lakes and swamps near the 
coast, is extremely prejudicial to health; and by incautious 
exposure to this, either early in the morning or late in the 
evening, the fatal seeds of the Malagasy fever may be so 
deeply received into the human constitution as never to be 
eradicated. In the central parts of the island, and in 
Ankova, said to be the most salubrious province in Mada¬ 
gascar, the fever does not exist, though here, occasionally, 
persons who have been affected on the coast, fall victims 
under a relapse. 
The great elevation of the province of Ankova, perhaps 
five or six thousand feet above the level of the sea, the 
absence of forests, the general dryness of the soil, the 
partial extent to which luxuriant vegetation is spontaneous, 
and the cultivation of many of the marshy parts of the soil, 
will be sufficient to account for its salubrity. The weather 
