Properties.—Foxglove is without odor in the recent state, but acquires a faint narcotic odor when dried. The color of the dried leaf is a dull pale green, modified by the whitish down upon the under surface; that of the powder is a fine deep green.
Constituents.—Digitalein, Digitonin, Digitalin and Digitoxin, the latter is most poisonous and active. Said to be cumulative.
Dose.—Digitalis leaves, horses, 15 gr. to 1 dr.; cattle, 30 gr to 11⁄2 dr.; sheep and pigs, 5 to 15 gr.; dogs, 1⁄2 to 3 gr.
Active Principles.—Digitoxin—It occurs in crystals, soluble in alcohol and chloroform, slightly in ether, and insoluble in water; said to be cumulative.
Dose.—Horses and cattle, 1⁄8 to 1⁄4 gr.; dogs, 1⁄250 to 1⁄50 gr.
Digitalein, an amorphous, bitter substance, soluble in water and alcohol and non-cumulative.
Dose.—Same as digitoxin.
Digitalin, a very bitter, crystalline substance, soluble in alcohol, and slightly soluble in water and ether.
Dose.—Same as for digitoxin.
Digitonin, resembling or identical with saponin of senega. White, amorphous powder, soluble in water. It is a heart depressant, muscular paralyzant and powerful irritant, besides being antagonistic to digitalis. In addition to these principles there are: Digitin, an inactive substance. Digitalic and antirrhinic acids. Tannin coloring matter, starch, sugar, gum, a volatile oil, salts, etc., common to most vegetables.