communication of the disease. It is certainly, therefore, an epidemic,
not a contagious disease; and calls on the chemists for some mode
of purifying the vessel by a decomposition of its atmosphere, if
ventilation be found insufficient. In the long scale of bilious fevers,
graduated by many shades, this is probably the last and most mortal
term. It seizes the native of the place equally with strangers. It has
not been long known in any part of the United States. The shade
next above it, called the stranger's fever, has been coeval with the
settlement of the larger cities in the southern parts, to wit, Norfolk,
Charleston, New Orleans. Strangers going to these places in the months
of July, August, or September, find this fever as mortal as the genuine
yellow fever. But it rarely attacks those who have resided in them
some time. Since we have known that kind of yellow fever which is no
respecter of persons, its name has been extended to the stranger's
fever, and every species of bilious fever which produces a black vomit,
that is to say, a discharge of very dark bile. Hence we hear of yellow
fever on the Allegany mountains, in Kentucky, &c. This is a matter
of definition only: but it leads into error those who do not know how
loosely and how interestedly some physicians think and speak. So far
as we have yet seen, I think we are correct in saying, that the yellow
fever, which seizes on all indiscriminately, is an ultimate degree of
bilious fever, never known in the United States till lately, nor farther
south, as yet, than Alexandria, and that what they have recently called
the yellow fever in New Orleans, Charleston, and Norfolk, is what has
always been known in those places as confined chiefly to strangers, and
nearly as mortal to them, as the other is to all its subjects. But both
grades are local: the stranger's fever less so, as it sometimes extends
a little into the neighborhood; but the yellow fever rigorously so,
confined within narrow and well defined limits, and not communicable
out of those limits. Such a constitution of atmosphere being requisite