Smelling, one of the external senses is that faculty by which are enabled to distinguish the odour of different substances. It is exercised by means of papillae, or little warts of the olfactory nerves, which are distributed throughout the nasal membrane; and convey volatile exhalations to the sensorium, exciting impressions of sweet, sour, fetid, or aromatic according to their respective nature.

This sense is intimately conected with that of taste; and, in some respects, is more valuable than the latter; as animal beings are thereby enabled to discover un-wholesome substances, without exposing themselves to danger. Thus brutes, and particularly dogs, possess a more acute smell than the human race; for this is their only guide in searching for food ; while man, being endowed with superior faculties, can dispense with such sagacity. Nevertheless, remarkable instances of acuteness of smell, in the rational creation, have some-times occurred. - See the article Odour.