ndard work on Materia Medica
for many centuries after his death. He compiled an account of all the
materials in use medicinally, and gave a description of their properties
and action. This entailed great knowledge and industry, and is of value
as showing what drugs were used in his time. Since then practically the
whole of Materia Medica has been changed. He held largely to the
orthodox beliefs of Dogmatism, but a great deal of what he recommends is
not comprised in the doctrines of this sect, and is decidedly Empirical.
It is difficult or impossible to identify many of the drugs referred to
by Dioscorides, partly because his descriptions are brief, partly
because the mistakes of his predecessors are found in his book.

He exercised as much authority in Materia Medica as Galen did in the
practice of medicine, and the successors of each were content, in the
main, to follow blindly. A large work was published in England in 1806
to illustrate the plants of Greece described in the treatises of
Dioscorides.

_Cassius Felix_ is supposed to have lived in the first century of our
era, but practically nothing is known of his history. He wrote a book on
medicine consisting of eighty-four questions on medical and physical
subjects and the answers to them.

In A.D. 79, after the eruption of Vesuvius, there was a great pestilence
in Rome, which historians ascribed to the pollution of the air by the
eruption. Fugitives crowded into Rome from the devastated part of the
country, and there was great poverty and an accumulation of filth in the
city, which was, doubtless, the true cause of the pestilence. Treatment
of fever at that time was very imperfect at the best, and proper means
of prevention and treatment were entirely absent in time of pestilence.
It has been computed that ten thousand people died daily at that time in
Rome and the surrounding district. Excavations at Pompeii have done a
great deal to reveal the state of surgical knowledge towards the end of
the first century of our era. Professor Vulpes has written an account of
the surgical instruments recovered from the ruins, and there is a
collection of ancient surgical instruments in the Naples museum. Vaginal
and rectal specula have been found: also a forceps for removing
fractured pieces of bone from the surface of the brain. There is an
instrument considered by Professor Vulpes to have been used as an artery
forceps. Other instruments discovered are: Forceps for removin