DBook II LENTICULAR FEVER—TVPHUS 111

which the populace lacks, can take greater precautions against
the sort of contagion that is transmitted from one person to
another; but they can defend themselves less well than the
populace from the contagion that depends on the air, since that
sort of contagion, though common to all, is more prone to at—
tack those who are rather delicate and less robust, and those
who are more full—blooded and of less dry temperament, and
the nobility have these characteristics because of their luxury
and life of ease. 'The populace, on the other hand, are more
robust and of drier temperament, because they exert them—
selves strenuously, and their diet is more frugal.

'This, then, is the behavior of lenticular fevers, and these are
the causes that produce them. Now I will speak of true pestif—
erous fevers.