some
length of time uninterruptedly, " has a marked effect on the nervous
centres, causing giddiness, sleeplessness, chronic itching of the
skin, and muscular tremblings of the arms, and legs."
Thus
also Wilmer testifies about Zinc " The action of extremely small doses,
if their use is prolonged, may produce a general decay of strength,
with prostration of the nutritive functions ; the intellectual
faculties become likewise impaired ; the beats of the heart become slow
and feeble ; whilst the walking powers, and the general bodily
endurance are enfeebled to a high degree." The phosphide of Zinc, given
in doses of the seventy-second part of a grain, has been found to
produce severe frontal stabbing headache. So, it would certainly seem
that to have hollow teeth stopped with pure Gold-leaf, though more
costly, is much the safer plan.
Concerning human saliva a remarkable statement made by Bartholomew Anglicus {On the Properties of Things, 1250),
is on record : " The spittle of a man fasting hath, in a manner,
strength of privy infection. For it grieveth and hurteth the blood of a
beast, if it come into a bleeding wound, and is medlied with the blood.
And that peradventure is, as saith Avicenna, by reason of rawness. And
therefore it is that holy men tell that the spittle of a fasting man
slayeth serpents, and adders ; and is venom to venomous beasts, as
saith Basil."
Whilst
discoursing of false teeth, to make amends for the losses within the
mouth caused by advancing age, we may mention the somewhat alarming
theory (at least as regards men who are more than half a century old),
which has lately been revived by Professor Osier; whose fixed notion is
that after their sixtieth year men are practically useless to the
State, and to
