case, it would not explain the phenomena, for, when ten grains of the
preparation in question are taken daily, scarcely a day elapses before
mercury can be detected in the secretions, and yet hydrargyriasis is not
produced; while when one grain is taken, and this condition follows, the
most delicate chemical examination fails to discover mercury in any of
the fluids or tissues of the body.

[Footnote 1: "Physiologic Pathologique," Paris, 1828, t.i., p. 44.]

Begin's definition scarcely separates idiosyncrasy from temperament,
whereas, according to what would appear to be sound reasoning, based
upon an enlarged idea of the physiology of the subject, a very material
difference exists.

Idiosyncrasies are often hereditary and often acquired. Two or more may
exist in one person. Thus, there may be an idiosyncrasy connected with
the digestive system, another with the circulatory system, another with
the nervous system, and so on.

An idiosyncrasy may be of such a character as altogether to prevent an
individual following a particular occupation. Thus, a person who faints
at the sight of blood cannot be a surgeon; another, who is seized with
nausea and vomiting when in the presence of insane persons, cannot be a
superintendent of a lunatic asylum--not, at least, if he ever expects to
see his patients. Idiosyncrasies may, however, be overcome, especially
those of a mental character.

Millingen[1] cites the case of a man who fell into convulsions whenever
he saw a spider. A waxen one was made, which equally terrified him. When
he recovered, his error was pointed out to him. The wax figure was put