38 



On Malaria on Ship-hoard, By Dr. Mac CuUoch. 



If in the former papers on Malaria, to which you gave admis- 

 sion in your Journal, I took occasion to notice the production 

 of this poisonous substance in ships, I submit to your judgment 

 as to the propriety of entering on this particular branch of that 

 question in more detail : partly on account of its great import- 

 ance, partly also because of the very persevering mistakes 

 which appear to have been committed on this point, and still 

 more, as you justly remark, because that which was likely to 

 have been passed with little notice in a general sketch of the 

 entire subject, is more likely to attract the attention of those 

 whom it may concern, when thus separated under a specific 

 title, and treated somewhat more fully than was formerly 

 admissible. 



If it has not been an unvarying opinion that the fevers 

 occurring in ships, and particularly those breaking out at sea, 

 are of a contagious nature, or appertaining to Typhus, (to use 

 a term now become popular,) I should find some difficulty, at 

 this moment, in producing any opinions to prove that they 

 were thought to appertain to the Remittent, or were fevers 

 produced by miasma or malaria, and not by contagion ; except 

 at least in these very unquestionable, or unquestioned, cases, 

 where the disease attacks the patient in a tropical climate, or 

 other analogous country, in consequence of communication 

 with the shore. On the contrary, I should, I believe, be safe in 

 saying, that almost every fever, perhaps even every remarkable 

 occurrence of this nature in a ship, has been viewed as an 

 example of contagious fever, or as a true Typhus ; while the 

 treatment has of course been modified by that opinion. 



Nor is this matter of surprise. I have shown in the Essay 

 on Malaria, that throughout Britain generally this error has 

 been extremely prevalent, for at least many years : while it 

 might be curious to investigate the causes, whence it has arisen 

 that we, of this day, had, on this subject, forgotten the 

 knowledge of our predecessors, the Sydenhams and Lobbs, 

 though it is an inquiry in which I ought not to indulge in this 



