Marco-Marci speaks of a monk at Prague, who, when any thing was brought
him, distinguished, by its smell, with as much certainty as the best nosed
dog, to whom it belonged, or by whom it had been handled. It was also said
of him, that he could accurately distinguish, in this manner, the virtuous
from the vicious. He was much devoted to the study of natural philosophy;
and, among other things, had undertaken to oblige the world with precepts
on the sense of smelling, like those we have on optics and acoustics, by
distributing into certain classes a great number of smells, to all of which
he had given names; but an untimely death cut him off in the midst of these
curious researches.

The guides who accompany travellers on the route from Smyrna or Aleppo, to
Babylon, have no other signs in the midst of the deserts, to discover their
distance from the place of destination, than the smell of the sand alone,
by which they determine with certainty. Perhaps they judge by the odour
exhaled from small plants, or roots, intermixed with the sand.

Physicians, in visiting the sick, have been known to form a prognostic,
before having seen the patient, from the effluvia of the sick-room. Those
who are in the habit of visiting the insane, know the peculiar odour that
characterises that dire calamity; and it was remarked of the plague, that
it had "a scent of the flavour of mellow apples."

It is said that monkeys possess this power of discrimination in a very
eminent degree. A story is told of a lady who had a pet of this
description, whom she made her constant companion, and who suddenly,
without any apparent cause, forsook her, and could not be persuaded to
re-enter her chamber. The lady was at that time infected with measles,
which shortly after appeared upon her; but, on her perfect recovery, the
monkey returned to her with his usual familiarity. Some time after, the