5i§ JAMAICA. 



the firil attack ; many others fuffer no iUnefs at all from the change, 

 but bear it well ; which proves, that licknefs or a fever was not re- 

 quired to prepare or adapt them to it. The thorough and proper 

 feafoniug to fuch a climate is brought about effeftually by remaining 

 in it for Ibme length of time ; and all fudden changes from cold to 

 heat, or heat to cold, produce nearly limilar effecfls. Thus, if 500 

 feamen or foldlers pafs from England to the Weft Indies, fetting out 

 in very cold weather, and arriving there after a quick voyage, many 

 of them will be feized with a diarrhoea, and with violent and mortal 

 fevers, if they indulge, foon after their arrival, in rum nenjoly di /Filled. 

 But, if the fame men are kept at fea, and the fliip does not put into 

 any unhealthy port, during the fickly feafon of the year, thefe men, 

 after being twelve months in the Weft Indies, will become perfedly 

 feafoned to the climate, and enjoy as good a flate of health, as if they 

 were in England. 



So, if the fame men, after being fome years in the Weft Indies, are 

 relieved, and arrive on the Englifli coaft, in the winter time, they 

 will be again feized with diarrhoeas j the cure and removal of 

 which will intirely depend on keeping the patients warm. On their 

 change to the hot climate, the humours, unable to pafs off faft enough 

 by the outlets of perfpiration, fall on the bowels. On their return 

 from a hot to a cold climate, the outlets by perfpiration being fud- 

 denly clofed, the humours are repelled, and driven again upon the 

 fame parts ; and the keeping the patients warm is no more than re- 

 calling their bodies to the fame glow to which they had lately beeii 

 accuftomed, and thereby promoting a free difcharge by the Ikin. 



It has been obferved, that mulkeetos are intolerably numerous in 

 thofe places in the Weft-Indies, which are leaft adapted to hu- 

 man habitation. They are found in the greateft fwarms among 

 lagoons, and fwamps on the fea coaft, and m little creeks flieltered 

 with mangrove trees ; in gullies which contain any ftagnant water; 

 in puddles on the flat country after the rainy feafons, and in river- 

 courfes in dry weather, where the water refts in detached hollows, 

 and becomes corrupted from the fermentation of aquatic weeds, 

 and fubfided fcum. Sometimes, I have known them driven from 

 their Ikulking holes, by the violence of ftrong fea breezes, to a con- 

 fiderable diftance up the country; but in general among the moun- 

 tains. 



