however, that if the patient will close firmly his mouth and nose and
blow hard, the escape of air through the fissured bone will reveal the
presence of the fracture (f. 88a). In the treatment of such fissures
he directs that the scalp wound be enlarged, the cranium perforated
very cautiously with a trepan (_trepano_) at each extremity of the
fissure and the two openings then connected by a chisel (_spata_?),
in order to enable the surgeon to remove the discharges by a delicate
bit of silk or linen introduced with a feather. If a portion of the
cranium is depressed so that it cannot be easily raised into position,
suitable openings are to be made through the depressed bone in order
to facilitate the free escape of the discharges.

Gunshot wounds were, of course, unknown in Gilbert's day. In a chapter
entitled "_De craneo perforato_" he gives us, however, the treatment
of wounds of the head produced by the transfixion of that member by an
arrow. If the arrow passes entirely through the head, and the results
are not immediately fatal, he directs the surgeon to enlarge the wound
of exit with a trephine, remove the arrowhead through this opening,
and withdraw the shaft of the arrow through the wound of entrance. The
wounds of the cranium are then to be treated like ordinary fractures
of that organ (f. 88c).

In wounds of the neck involving the jugular vein (_vena organica_),
Gilbert directs ligation of both extremities of the wounded vessel,
after which the wound is to be dressed (but not packed) with the
ordinary dressing of egg-albumen.

Wounds of nerves are treated with a novel dressing of earthworms
lightly beaten in a mortar and mixed with warm oil, and he professes
to have seen nerves not only healed (_conglutinari_), but even the