Destroyed by cold, conveyed from place to place in
garments, and attached to the walls of houses. How can we explain
why, for the space of eighteen years prior to 1794, there was not a
single instance of the vomito at Vera Cruz, though the concourse of
unacclimated Europeans and of Mexicans from the interior, was very
considerable; though sailors indulged in the same excesses with
which they are still reproached; and though the town was not so
clean as it has been since the year 1800?
The following is the series of pathological facts, considered in
their simplest point of view. When a great number of persons, born
in a cold climate, arrive at the same period in a port of the
torrid zone, not particularly dreaded by navigators, the typhus of
America begins to appear. Those persons have not had typhus during
their passage; it appears among them only after they have landed.
Is the atmospheric constitution changed? or is it that a new form
of disease develops itself among individuals whose susceptibility
is highly increased?
The typhus soon begins to extend its ravages among other Europeans,
born in more southern countries. If propagated by contagion, it
seems surprising that in the towns of the equinoctial continent it
does not attach itself to certain streets; and that immediate
contact* does not augment the danger, any more than seclusion
diminishes it.
