A gum-resin long known for its aromatic properties. Internally given, it is stimulant and tonic, and is an ingredient in some preparations intended to act upon the bowels or to restore suspended menstruation. For home use, the tincture of myrrh is very serviceable in the care of the mouth. A few drops of it in a little water, say about twenty drops in a quarter of a tumblerful, used as a mouth-wash, will correct a bad odor in the breath. Such a wash may be used with advantage twice daily, in cleaning the teeth. When the teeth begin to decay, a strong myrrh wash, often used, will check or retard their destruction. If a hollow tooth becomes tender, and begins to ache, pure tincture of myrrh put into it will sometimes stop the trouble at the beginning. If, however, it does not at once give relief, the stronger application of creosote should follow it.

Nitrate of Silver, or lunar caustic. Physicians often use this as an alterative application to the throat, eyes, or ulcerated skin, in certain states and stages of inflammation. It is also sometimes given in pill as a medicine ; most beneficially in chronic {gastritis) inflammation of the stomach. Dose, internally, a quarter of a grain (usually with as much of opium), thrice daily, gradually increased, when it does good, to nearly or quite a grain. It was formerly much employed in the treatment of epilepsy. When long continued, it has sometimes dyed the skin, making the face almost as black as ink.