tone, burnt
stag's horn, nitre, alum, rock salt, burnt roots of iris, aristolochia,
and reeds. All of these substances should be carefully reduced to powder
and then mixed. His favorite liquid dentifrice contained the following
ingredients,--half a pound each of sal ammoniac and rock salt, and a
quarter of a pound of sacharin alum. All these were to be reduced to
powder and placed in a glass alembic and dissolved. The teeth should be
rubbed with it, using a little scarlet cloth for the purpose. Just why
this particular color of cleansing cloth was recommended is not quite
clear.

He recognized, however, that cleansing of the teeth properly often
became impossible by any scrubbing method, no matter what the dentifrice
used, because of the presence of what we call tartar and what he called
hardened limosity or limyness (_limosite endurcie_). When that condition
is present he suggests the use of rasps and spatumina and other
instrumental means of removing the tartar.

Evidently he did not believe in the removal of the teeth unless this was
absolutely necessary and no other method of treatment would avail to
save the patient from continuous distress. He summarizes the authorities
with regard to the extraction of teeth and the removal of dental
fragments and roots. He evidently knew of the many methods suggested
before his time of removing teeth without recourse to instrumental
extraction. There were a number of applications to the gums that were
claimed by older authors to remove the teeth without the need of metal
instruments. We might expect that Chauliac would detect the fallacy with
regard to these and expose it. He says that while much is claimed for
these methods he has never seen them work in practice and he distrusts
them entirely.

The most interesting phase of what Guy de Chauliac has to say with
regard to dentistry is of course to be found in his paragraphs on the
artificial replacement of lost teeth and the subject of dental
prosthesis generally. When teeth become loose he advises that they be
fastened to the healthy ones with a gold chain. Guerini suggests that he
evidently means a gold wire. If the teeth fall out they may be replaced
by the teeth of another person or with artificial teeth made from
oxbone, which may be fixed in place by a fine metal ligature. He says
that such teeth may be serviceable for a long while. This is a rather
curt way of treating so large a subject as dental prosthesis, but it
co