Terebinthina (Canadensis) U. S. P., Eighth Revision, but the oil of turpentine and the rectified oil of turpentine, not designated as Canadian in trade, are usually obtained from Pinus palustris. Canada turpentine is called in the U. S. P., Balsam of Fir and Canada Balsam. The tree is known as Hemlock Spruce or Abies balsamea. There is some conflict over nomenclature as regards Abies balsamea and Abies canadensis, the latter having a very astringent bark; but all turpentines involved are much alike. Neither must be regarded as Black Spruce, the Abies nigra of some writers. Abies excelsa is a European variety from which Burgundy Pitch is derived. Abies pectinata yields Strassburg Turpentine. Abies sibirica yields Oil of Pine Needles, of the British Pharmacopeia. Abies Fraseri is our own Southern Balsam Fir. The name "Pinus" is conflicted with some of these. See "Tar-Vegetable." A proprietary "Pine Oil" is made in Florida and other Southern States from the long-leaf Southern pine, or Pinus Australis, which is heavier and more aromatic than the U. S. P. oil of turpentine. Abies nigra possesses irritating properties which militate against its use.

Pharmacology

Pinene occurs in oil of pine, turpentine, and in some of the essential oils, which acquire in time a terebinthinate odor. Oxypinene, a new product, is an ozonized pinene. Terpenes oxidize into resins. These two are the interesting agents in Abies, pinene being the important one. It is related to the benzenes and is toxic to living protoplasm, being an antiseptic more toxic to molds than to bacteria (Bucholtz). It penetrates the skin, dilates the vessels, and is rubefacient. Internally it is irritant, causing vomiting and purging and polymorphonuclear leucocytosis, and it is toxic in large doses to the central nervous system.

Small amounts are excreted unchanged by the lungs and skin, and by the kidneys with glycuronic acid, which produces diuresis; but large doses decrease the flow of urine. Turpentine is an unsafe anthelmintic. The positive chemotactic properties tend to retain the leucocytes in the blood-stream (Pohl), thus limiting purulent action in so-called "catarrhal" difficulties.

Therapeutics

Turpentine is a rubefacient valuable in affections of the chest and abdomen. It is applied in the form of a stupe.

Turpentine liniments are valuable in myalgia and where slight rubefacient influences are desirable. The various tars are preferable in cutaneous diseases. As an antiseptic, turpentine may be used in emergency, especially in penetrating wounds; but do not depend upon its killing the germs of tetanus. Canada pitch produces mild rubefaction, but is now little used. The inhalation of turpentine vapors decreases bronchial secretion and is useful in bronchitis.

There is no doubt of the utility of the terebinthi-nate remedies in catarrhal troubles, especially in subacute and chronic bronchitis. Terebene, in 3- to 6-drop doses, is probably the best for administration in official form; but I prefer Apinol, listed in "New and Nonofficial Remedies" as made from the Southern long-leaf pine. It is so slightly irritating that it may be given up to 15-drop doses on sugar cubes. Solupin is of a similar composition. Oil of Pine Needles, long used in England, is now listed in "New and Nonofficial Remedies." It is vastly more agreeable than is turpentine, and is an excellent inhalant. It is expectorant in doses of 1 to 6 drops. Terpin Hydrate is inferior to both of these products, but is popular in "cough syrups" in doses of one-half to one grain, and in elixirs which are strongly alcoholic in doses up to 2 grains.

Many physicians employ turpentine oil in the treatment of typhoid fever when there is a tendency to muttering delirium. It is given in emulsion. While rational, I believe we have better resources in the treatment of typhoid; but when the abdomen is distended it certainly acts well. Use the rectified oil in 10-drop doses in emulsion, which is an official U. S. P. preparation of 15 per cent strength.

Turpentine is now little used in genito-urinary affections, and it has been abandoned as an antidote in phosphorus poisoning. Its hemostatic influences are fairly positive, but its irritating properties constitute an objection. Tincture of the bark of Abies Canadensis have been used for an astringent effect, but other vegetable drugs are to be preferred.

Administration

This has been considered in the preceding section. Never give crude turpentine internally. The preparations noted are preferable in every way.