Book I CONTAGION 61

influence of the stars, are nevertheless very often accompanied
by the phenomena that occur per se; and there is no reason why
certain phenomena should not arise from the heavenly bodies
by accident, and that very often. Now the sidereal condi—
tions which are most apt to produce new and serious effects are
those in which several of the planets are in conjunction; especial—
ly under the influence of certain of those important stars that
are called 'fixed'. In fact, when conjunctions of this sort
take place, they nearly always produce some notable and por—
tentous birth. Perhaps one ought to treat this question more
exhaustively.

Seabies, porrigo, papules and leprosy rove over the whole
periphery of the body, while achores, bald spots,** ophiasis
and the like affect the head. 'The germs of all these affections
are denser and less sharp (i.e. pointed) than those that attack
the deep—seated parts of the body, for the latter germs are more
subtile, sharper, and more analogous with the spiritual elements.
Again, of those that are harbored in the periphery, some attack
the outer skin, others sink deeper in and are of denser substance,
for example sphacelus (gangrene) esthiomeni,*5 carbuncles, ele—
phantia,** the malady syphilis and the like. Germs so con—
stituted as to be very sharp and subtile infect very quickly and
attack the heart, especially through the breath, and they are
analogous with the spirits and the more volatile humors. But
those germs whose substance is denser and which are analogous
with the denser humors, ereep in (invade) slowly, as for instance
the germs of syphilis and rabies; but the animal, when dead,
does not preserve the contagion by which it was dominated
when alive, because the germs of the contagion have perished
together with the innate heat.

Bodies that are unclean and very moist, and have the pores
of their flesh stopped up, are especially disposed to those con—
tagions that develope within us originally; but bodies that have
open and slack pores and are also hot and moist are disposed
rather to those contagions that come to us from without. The
receptivity is difficult and slower in persons who have a cold,
dry and dense constitution of body. That is why the old, both
men and women, are less easily infected than the young. Never—
theless we must take into aeccount the analogies?? of those con—
tagions which attack one person rather than another.  People
who spend their lives in idleness have less receptivity than those