Book III OF LENTIOCULAR FEVER—TVPHUS 243

made of cornel berries. / But others are merely harsh, for example
a& mixture of water and pomegranate wine or vinegar, or acetose
syrup, or eitron juice, orange juice, lemon juice and the like.
"These may safely be allowed, for they can do no harm but may
do great good, because they are in potency dry, and are cold.

As regards powders: one may say, in general, that of those
which are triturated, some on account of their hardness and
dryness always remain of such a consistency that, however
vigorously you may triturate them, they can never be reduced
to flour, that is, into particles so fine that they cannot be per—
ceived in aection as particles; for example segments of iron,
copper, marble, glass and many kinds of stone. But there are
others which can very well be reduced to flour, such as pearls,
corals,6* and many gems; likewise sphragis, Armenian bole
and many other earths. Again, certain powders, when tri—
turated, cannot be mixed with liquids in such a way as to coalesce
with them. However there are certain others which do so
combine and coalesce that it is impossible by any sense to dis—
tinguish the particles per se in action. Now those particles
which cannot be triturated into fine flour, or do not coalesce
well with liquids, ought not to be used in this sort of fever,
because they will settle either in the stomach or the intestines,
or will not be distributed to the localities where they are needed;
and when thus undigested they are very harmful. But those
which can be thoroughly triturated into flour, and which coalesce
thoroughly with liquids, you need not fear to use, or rather you
should not fail to prescribe them, since they are both materially
and spiritually antipathetic to contagions. Moreover, when
intermixed with the humors, they prevent their putrefaction
in yet another way; and they have been made so subtile and
fine that they cannot cause obstruction or hinder any expul—
sion. — Of this kind are Lemnian sphragis, Armenian bole, pear!s,
eoral, jacinth, sapphires, tormentilla, and what is called bistorta,
hartshorn, the horn of the unicorn, scordium, and many others
of the same sort.

As for the emerald,*7 to deal with it separately, for my part
I do not find attributed to it in the writings of the ancients any
such preäminent quality as certain modern doctors claim for it.
Now we may speak about the virtues of anything, either from
our experience or from reasoning.  In this case I think it would
be very hard to acquire sufficient experience; for even supposing