SUMACH, or SWAMP SUMACH (Riots Toxicodendron,), a North American shrub, possessing peculiar properties, from which it has been named also the Trailing Poison Oak. The leaves, which are trifoliate, thin, shining when fresh, of a dark-green colour, are the only parts officinal in this country. But the leaves, branches, and flowers contain a milky juice which blackens on exposure to the air, and may be used as an indelible ink when applied to cotton or linen. Besides this very acrid milk, the plant, when not exposed to the sun's rays, by growing in the shade, or during the night, exhales a hydrocarburetted gas, which acts very potently on persons of a peculiar susceptibility, when exposed to it. In two or three days 'after touching or being very near the plant, the skin inflames and swells, being attended with intense burning pain. If the face be affected, the eye-lids are so tume fied as to close up the eyes ; and the whole bead is swelled and covered with little blisters containing serum. Occasionally the whole body is
enormously swollen and covered with similar vesicles. When the inflammation and swelling have subsided, the skin desquamates, and an intolerable itching is felt for several days afterwards. These symptoms closely resemble erysipelas, and are moderated by treatment suited to that complaint. Professor Barlow states that the best appli cation is a weak aqueous solution of bichloride of mercury. All persons however should avoid touching any sumach which has milky juice.
The leaves, or an extract of the inspissated juice of this plant, have been recommended in several diseases, particularly herpes, paralysis, and consumption. It is little used in this country, but it appears entitled to some confidence in local paralysis, such as that of the jaw. It must be given with caution, as large doses act like narcotico-acrid poisons.