correctness of Daremberg's statement that Galen was the leader of the most advanced school of experimentation:—
The more strongly the thorax, in its exertion of a compressing
force, tends to drive the blood (out of the heart), the more tightly
do these membranes (the sigmoid valves) close the opening.
Invested in a circular manner from within outward, extending
throughout the entire circumference of the interior of the vessel,
these membranous valves are, each one of them, so accurately
patterned and so perfectly fitted that when they are put upon the
stretch by the column of blood, they constitute a single large
membrane which closes (watertight) the orifice. Pushed back by
the return flow of the blood, they fall back against the inner surface
of the vein, and permit an easy passage of the blood through
the amply dilated orifice (which they, an instant before, closed so
perfectly).
(Translated from Book VI., Chapter XI., of Daremberg's French version of the works of Galen.)
In his comments upon the account of the sigmoid valves
which I have just quoted, Daremberg says that the description
of these structures given by Erasistratus at least four
hundred years earlier is admitted by Galen to be so correct
that it would scarcely be possible to furnish a better one.
Galen's Remarks upon the Subject of Diagnosis.—In the treatise entitled "On the parts of the Body Affected" (Book II., Chapter X.) Galen gives the following advice with regard to the method which it is desirable to adopt when one wishes to ascertain which part or organ is affected, what is the nature of the disease there located, and whether it is primary in its nature or secondary to some affection of earlier development:—
It should have been the special duty of Archigenes, who appeared
on the scene next in order after a series of the most illustrious
physicians,[1] to infuse more light into medical teaching. Unfortu-**
- ↑ Hippocrates, Herophilus, Erasistratus, Asclepiades, Themison, Celsus, Soranus and Athenaeus. Daremberg calls attention to the fact that, although we possess to-day only a few fragments of the writings of Archigenes, those few are of such a degree of excellence that we may well ask ourselves whether Galen was not perfectly justified in placing such a high estimate as he appears to have done upon the merits of this writer,—and that, too, notwith-*
