OF THE MARSH POISON. 275 



which remained the whole autumnal season in the most pesti- 

 ferous portion of that unhealthy country, without its suffering 

 in any remarkable degree from endemic fever. Dysentery 

 was almost the only serious disease they encountered. Remit- 

 tent fever was nearly unknown, and intermittent occurred 

 very rarely ; but the preceding summer season had been wet 

 and cold to an unexampled degree ; during the whole of the 

 service we had constant rains, and the whole country was one 

 continuous swamp, being nearly flooded with water. In the 

 year 1810, a British army at Walcheren, on a soil as similar as 

 possible, and certainly not more pestiferous, but under the dif- 

 ferent circumstances of a hot and dry preceding summer, in- 

 stead of a wet and cold one, suffered from the endemic fever 

 of the country to a degree that was nearly unprecedented in 

 the annals -of warfare. 



As I intend, in another part of this paper, to treat fully of 

 the nature of the localities in the West Indies, I shall pass 

 over at present my next experience of endemic fever during 

 three years service in the Island of St Domingo, and proceed 

 to state what I observed on this subject in Portugal and 

 Spain : In the course of the Peninsular War, during the 

 autumnal campaign of 1808, our troops, after the battle of Vi- 

 meira, were comparatively healthy. The soil of the province 

 around Lisbon, where they were quartered, is a very healthy 

 one, (a slight covering of light sandy soil on a substratum of 

 hard rock, which is almost always so bare, that water can sel- 

 dom be absorbed into it to any depth, but is held up to speedy 

 evaporation). The season was fully as hot a one as is ordina- 

 rily seen in that country, but dysentery was the prevailing 

 disease. Early in 1809 the army advanced to Oporto, for the 

 expulsion of the French under Marshall Soult from Portugal 

 which, during a very cold and wet month of May, (for that 



country,) 



