Balsam (from Gr. βάλσαμον, through Lat. balsamum, contracted by popular use to O. Fr. basme, mod. Fr. bâme; Eng. balm), a term properly limited to such resins or oleo-resins as contain benzoic acid or cinnamic acid or both. Those balsams which conform to this definition make up a distinct class, allied to each other by their composition, properties and uses. Those found in commerce are the balsam of Peru, balsam of Tolu, liquid storax and liquidambar. Balsam of Peru is the produce of a lofty leguminous tree, Myroxylon Pereirae, growing within a limited area in San Salvador, Central America and introduced into Ceylon. It is a thick, viscid oleo-resin of a deep brown or black colour and a fragrant balsamic odour. It is used in perfumery. Though contained in the pharmacopeias it has no special medicinal virtues. Balsam of Tolu is produced from Myroxylon toluiferum. It is of a brown colour, thicker than Peru balsam, and attains a considerable degree of solidity on keeping. It also is a product of equatorial America, but is found over a much wider area than is the balsam of Peru. It is used in perfumery and as a constituent in cough syrups and lozenges.
Liquid storax or styrax preparatus, is a balsam yielded by Liquidambar orientalis, a native of Asia Minor. It is a soft resinous substance, with a pleasing balsamic odour, especially after it has been kept for some time. It is used in medicine as an external application in some parasitic skin diseases, and internally as an expectorant. An analogous substance is derived from Liquidambar Altingia in Java. Liquidambar balsam is derived from Liquidambar styraciflua, a tree found in the United States and Mexico. It contains cinnamic acid, but not benzoic acid.
Of so-called balsams, entirely destitute of cinnamic and benzoic constituents, the following are found in commerce: - Mecca balsam or Balm of Gilead, from Commiphora opobalsamum, a tree growing in Arabia and Abyssinia, is supposed to be the balm of Scripture and the βάλσαμον of Theophrastus. When fresh it is a viscid fluid, with a penetrating odour, but it solidifies with age. It was regarded with the utmost esteem among the nations of antiquity and to the present day it is peculiarly prized among the people of the East. For balsam of copaiba see Copaiba. Under the name of wood oil, or Gurjun balsam, an oleo-resin is procured in India and the Eastern Archipelago from several species of Dipterocarpus, chiefly D. turbinatus, which has the odour and properties of copaiba and has been used for the same purposes. Wood oil is also used as a varnish in India and forms an effective protection against the attacks of white ants. Canada balsam or Canada turpentine is the oleo-resin yielded by Abies balsamea, a tree that grows in Canada and the northern parts of the United States. It is a very transparent substance, somewhat fluid when first run, but thickening considerably with age, possessed of a delicate yellow colour and a mild terebinthous odour.
It contains 24% of essential oil, 60% of resin soluble in alcohol, and 16% of resin soluble only in ether. Its chief uses are for mounting preparations for the microscope and as a cement for glass in optical work.
The garden balsam is an annual plant, Impatiens balsamina, and the balsam apple is the fruit of Momordica balsamina, nat. order Cucurbitaceae.