Oleum Betulae Empyreumaticum and Tinctura Rusci.

BY THE EDITOR.

Three correspondents in New York have favored us with the information that Tinctura rusci is not a tincture of the obsolete butchers broom, as we suggested on page 33 of the January number, but that it is an alcoholic solution of birch oil, or rather birch tar, which is largely manufactured in Russia and Poland, from birch bark, by a process of descending distillation similar to that employed in the preparation of ordinary tar. This birch tar resembles wood tar in appearance, but has a peculiar penetrating odor, and is used in the manufacture of Russia leather, which owes to it its peculiar odor. Its common name is degutt or dagget, and it was formerly employed in medicine and in veterinary practice under the following names and synonyms: Oleum betulinum, s. rusci, s. russicum, s. moscoviticum, s. lithuanicum.

Birch tar contains, probably, the principal constituents of common wood tar. By distillation, A. Sobrero, in 1842, obtained a brown oily liquid, of a strong odor, lighter than water, and of an acid reaction. On fractionating this product near 100°C. a pale yellow oil was obtained having an agreeable odor, resembling that of turpentine and birch bark, and an acid reaction. After treatment with potassa and lime water it was again rectified, and had then a more agreeable smell, like birch bark. Its composition was found to be C₁₀H₁₆. It dissolves in alcohol and ether, and is a solvent for resins. Between —16° and —17°C. (about 2°F.) it congeals partly; its boiling point is 156°C. This is the only analysis of birch tar with which we are acquainted; the principle to which the strong odor of birch tar is due does not appear to have been chemically examined.

Recently, birch tar has been to some extent prescribed in New York in the form of tinctura rusci and pomatum rusci, occasionally simply as rusci. There does not appear to be any authoritative formula for either preparation; for, while one correspondent informs us that they are usually made by mixing one part of birch tar with three or four parts of alcohol, or the pomade with three or four parts of soft paraffin, another correspondent send us the following formula for the tincture:

Mix and filter.

This is Hager's formula for the external use of birch tar in rheumatism and gout, except that Hager orders 0.5 gram of each of the volatile oils.

Hager, in "Pharm. Praxis," gives, also, the following for Essentia Rusci:

Mix, and, after decantation, filter.

Birch tar has also been used in menorrhoea, piles, cancer, venereal ulcers, as an anthelmintic, and in intermittent fever, in doses of from 6 to 10 grains three times daily, usually in the form of pills. At present it seems to be mainly employed in skin diseases, and the pomade referred to above is often sold in New York as Hebrews tar pomade.

The American Journal of Pharmacy, Vol. 53, 1881, was edited by John M. Maisch.