36 



Oroonoko, the Cassiquiare, and even the limits 

 of the Portuguese possessions on the Rio Negro. 

 We were also indebted perhaps to this direction 

 given to our travels for the state of health we 

 enjoyed during so long an abode in the equinoc- 

 tial regions. 



It is well known, that Europeans, during the 

 first months after their arrival under the scorch- 

 ing sky of the tropics, are exposed to the great- 

 est dangers. They consider themselves as sea- 

 soned, when they have passed the rainy season 

 in the West India islands, at Vera Cruz, or at 

 Carthagena. This opinion is very general, 

 although there are examples of persons, who, 

 having escaped a first attack of the yellow fever, 

 have perished victims of the same disease in one 

 of the following years. The facility of being sea- 

 soned seems to be in the inverse ratio of the 

 difference that exists between the mean tempera- 

 ture of the torrid zone, and that of the country 

 in which the traveller, or planter, who changes 

 his climate, is born ; because the irritability of 

 the organs, and their vital action, are powerfully 

 modified by the influence of the atmospheric 

 heat. A Prussian, a Polander, or a Swede, is 

 more exposed on their arrival at the islands or 

 on the continent, than a Spaniard, an Italian, 

 or even an inhabitant of the South of France *. 

 With respect to the people of the north, the 



* New Spain, vol. ii, p. 754. 



