There are many agents of value in medical treatment which by their nature are unsuitable for application except in the form of unguents. These, however, are much less in vogue now than was formerly the case, and the bases used by the advanced pharmacist are no longer the same; lard and goose-grease have given place to vaseline and lanoline, which do not become rancid.

Whenever an ointment is prescribed, except for application to a wounded surface, it is generally understood to require gentle but continuous inunction for several minutes.