Materia medica and therapeutics : for physicians and students / by John B. Biddle.
- John Barclay Biddle
- Date:
- 1886
Licence: Public Domain Mark
Credit: Materia medica and therapeutics : for physicians and students / by John B. Biddle. Source: Wellcome Collection.
49/572 page 39
![Liniments [Liniinenta) are oily preparations designed for external use, usually thicker than water, but always liquid at the temperature of the body. Ointments {Unguenta) are preparations of a consistence like that of butter, made with lard or some other fatty substance. They are fitted for application to the skin by friction or inunc- tion. Most of the ointments become rancid when long kept, and it is therefore best to prepare them only as wanted for use. Petrolatum^ a substitute for vaseline, a straw-colored ointment made from petroleum, not decomposable, is a superior unguent for general purposes. The term ointment (unguentum) is applied to a mixture of 20 parts of yellow wax and 80 parts of lard. Cerates [Ceratd] are made of oil or lard, mixed with wax, spermaceti, or resin, with the addition of various medicinal sub- stances. They are of harder consistence than ointments, and do not melt when applied to the skin. The term cerate [cera- tum) is applied to a mixture of 30 parts of white wax and 70 parts of lard. Oleates (Oleata) are made by combining oleic acid with metallic bases or alkaloids. The combination is effected by rubbing them together in a mortar and is generally aided by heat. Plasters (Emplastra) are adhesive at the temperature of the body, and must generally be heated to be spread. Some sub- stances have sufficient consistence and adhesiveness to be made into plasters. Usually, however, medicinal substances, when employed in this form, are mixed with Lead Plaster or Litharge Plaster {Emplastrmn Plumbi), a compound of olive oil and litharge. Plasters are prepared for use by spreading them upon sheepskin, linen, or muslin, with a margin a quarter or half inch broad. Cataplasms or Poultices {Cataplasinata) are soft, moist sub- stances intended for external use. The common emollient poultice, employed to relieve inflammation and to promote sup- puration, is made by mixing bread-crumbs with boiling milk](https://iiif.wellcomecollection.org/image/b20386357_0049.jp2/full/800%2C/0/default.jpg)
