294 ON THE ORIGIN AND HISTORY 



alone ever venture to inhabit it, and when they see strangers 

 tarrying on the shore after night-fall, they never fail to warn 

 them of their danger. The same remark holds good in regard 

 to the greater part of the leeward coast of Martinique, or the 

 leeward alluvial basis of hills, in whatever part of the torrid 

 zone they may be placed, with the exception probably of the 

 immediate sites of towns, where the pavements prevent the 

 rain-water being absorbed into the soil, and hold it up to 

 speedy evaporation. 



For this, if there be a remedy, it must be found in the 

 powers of cultivation, ever opening the surface for the escape 

 of pestilential gases, and exhausting the morbific principle by 

 a constant succession of crops ; for wherever malaria prevails, 

 the uncultivated savannah, even though used for pasture, be- 

 comes infinitely more pestiferous than the plantation, and the 

 depopulated country falls completely under its dominion. 

 With the aid of the purifying sea-breeze, this course at the 

 British colony of Demerara, within six degrees of the equator, 

 has succeeded in rendering the cultivated portion of the deepest 

 and most extensive morass probably in the world, a healthy, 

 fertile, and beautiful settlement. I shall hot here enter into a 

 detailed account of the astonishing system of tide and flood- 

 gate drainage by which this delightful result has been esta- 

 blished and kept up, but hasten to a conclusion. 



It would be unphilosophical to suppose, that the marsh poi- 

 son, because other distempers, such as dysentery, co-exist with 

 it, ever produces any disease but the specific one of which it is 

 the acknowledged parent, varying, however, in form, and as a 

 modification of effect from the same cause, from the common 

 ague of the fens of Lincolnshire, through all the milder remit- 

 tent types, up to the aggravated yellow fever, or malignant re- 

 mittent of the West Indies ; and that variation, so certain and 



uniform, 



