314 On Malaria, 



on the boats' crews at the very instant of the recess of the 

 tide ; while its cause is rendered immediately sensible, by a 

 peculiar earthy smell, well known, even many miles at sea, as 

 brought off by the land-winds, and equally exciting fevers 

 among the ships' crews. 



Now, it is familiar that in our own country, fevers, and in 

 summer as usual, are common in our sea-ports ; while, from 

 the persistent errors on this subject, always attributed to 

 poverty, filth, confinement, and, of course, to contagion. That 

 this is not the real cause, is proved partly by the season to 

 which they are confined, if it was not by the fact that they 

 are really not contagious, but mistaken for such by being at- 

 tached to particular spots or houses ; and partly by that other 

 fact, that they will be found to appertain to the very kind of 

 sea-ports which I have described, and not to occur in deep 

 harbours or on clean and rocky shores. It is easy for any one 

 to conjecture where they ought to happen ; and any one who 

 ■will inquire, will find that the experience corresponds to the 

 theory as derived from the present view. 



It is so important, for many reasons obvious to medical 

 men, to distinguish between contagious fevers and those which 

 are not such, and the evils which arise from misstating marsh- 

 fever for typhus are so numerous, that I must be excused for 

 urging this subject as to all these last cases, and as to one also 

 of very great importance which is about to follow. And, in- 

 dependently of this medical importance, it is particularly neces- 

 sary in all that relates to prevention : since, as long as these 

 fevers shall be believed to be typhus, or to arise from any 

 other cause than what they really do, it is plain that it will be 

 impossible to apply any means of diminishing their numbers, 

 whether by avoidance of the causes, or by directly removing 

 or checking the influence of these. And I am sure that a 

 more accurate attention, recently bestowed on fevers by prac- 

 titioners, will confirm what I have said respecting the compa- 

 rative rarity of proper contagious fevers ; if these persons 

 have not yet agreed to refer them to malaria, and have not 

 learned to discover the various sources whence this is pro* 

 duced, and which I have here been attempting to point out 

 and explain. 



