THE AMERICAN TTI'HTJS. 
383 
during several months there may have been no sick person in 
the harbour, and no ship may have entered it. 
The typhus of America appears to be confined to the 
shore, either because persons who bring the disease disem- 
bark there, and goods supposed to be impregnated with dele- 
terious miasms arc there accumulated; or because on the 
sea-side gaseous emanations of a particular nature are formed. 
The aspect of the places subject to the ravages of typhus 
seems often to exclude all idea of a local or endemical origin. 
It has been known to prevail in the Canaries, the Bermudas, 
and among the small West India Islands, in dry places for- 
merly distinguished for the great salubrity of their climate. 
Examples of the propagation of the yellow fever in the in- 
land parts of the torrid zone appear very doubtful : that 
malady may have been confounded with remitting bilious 
fevers'. With respect to the temperate zone, in which the 
contagious character of the American typhus is more decided, 
the disease has unquestionably spread far from the shore, even 
into very elevated places, exposed to cool and dry winds, as 
in Spain at Medina-Sidonia, at Carlotta, and in the city of 
Murcia. That variety of phenomena which the same .epi- 
demic exhibits, according to the difference of climate, the 
union of predisposing causes, its shorter or longer duration 
and the degree of its exacerbation, should render us ex- 
tremely circumspect in tracing the secret causes of the 
American typhus. M. Bailly, who, at the time of the violent 
epidemics in 1S02 and 1 803, was chief physician to the colony 
of St. Domingo, and who studied that disease in the island of 
Cuba, the United States, and Spain, is of opinion that the 
typhus is very often, but not always, contagious. 
Since the yellow fever has made such ravages in La Guavra, 
exaggerated accounts have been given of the uucleauliness iu 
that little town as well as of Vera Cruz, and of the quays or 
wharfs of Philadelphia. In a place where the soil is extremely 
dry, destitute of vegetation, and where scarcely a few drops of 
water fall in the course of seven or eight months, the causes 
that produce what are called miasms, cannot be of very fre- 
quent occurrence. La Guayra appeared to me in general to 
be tolerably clean, with the exception of the quarter of the 
slaughter-houses. Tho sea-side has no beach oti which the 
remains of fuci or molluscs are heaped up ; hut the neigh- 
