Dr. Mac CuUoch on Malaria on Ship-board. 43 



of Alicante, which was the non-contagious, or marsh, *' yellow'* 

 fever, was mistaken, reversely, for the contagious one, and 

 managed accordingly, with very inconvenient results, if not with 

 similarly mortal ones. 



And that the readers for whom I am here writing may ap- 

 prehend generally what the consequences of these mistakes 

 have been, and are, and may be again, I will state the most 

 prominent points ; facts that have existed, and which have been 

 repeated, even very recently. In our own country and our 

 own fevers, the consequences under these errors are compara- 

 tively trifling ; yet the inconveniences, and even the mortality, 

 are far from being so inconsiderable as a superficial thinker, or 

 a person ignorant of medicine, would imagine. And what I 

 have to remark offers another interesting, if painful example, 

 of that class of fallacy arising from the influence of a popular 

 term. The yellow fever ; this term, like the word typhus, was 

 sufl[icient : it was reasoning and observation united. '• Yellow'* 

 fever had generally been a mar^h fever: it was sufficient, there- 

 fore, that to a fever, to any fever with this symptom, the term 

 yellow fever was applied, and the whole question became de- 

 termined without examination. When will mankind be freed 

 from the slavery to words ? — when mankind learns to think 

 and to reason. 



When the " yellow" fever, being the typhus, or contagi- 

 ous disease, has been supposed the marsh, or non-conta- 

 gious fever, the consequence has been neglect in intercept- 

 ing communication, and in all those precautions which stop 

 the progress of contagion ; the consequence has been mor- 

 tality, which might have been prevented by the simplest 

 precautions, and that mortality diffusing itself from town to 

 town, and from sea-port to sea-port, across half the globe. 

 This was the lamentable case of Gibraltar, very particu- 

 larly. When the " yellow" fever has been the marsh, or 

 non-contagious fever, the consequences have been different : 

 less mortal, it is true, but, perhaps, quite as vexatious, and, 

 municipally as well as commercially, far more troublesome. 

 Hence cordons drawn round towns, with other troublesome 

 and expensive arrangements to check an imaginary con- 

 tagion, destructive of personal liberty and commerce ; — hence 

 quarantine laws made and enforced against that which was 



