DOSE.--Horses and cattle, 2 to 4 drs.; sheep and pigs, 15 ms. to 1 dr.; dogs, 5 to 30 ms. This dose can be given every three hours to maintain the circulation of the skin; as a diaphoretic, the dose can and may be increased and combined with other diaphoretics. INCOMPATIBLES.--Its action is antagonized by ammonia, alcoholic stimulants, opium, camphor, etc. SYNERGISTS.--Aconite, veratrum viride, digitalis and arterial sedatives, generally increase the effects of arnica. ACTIONS.--Arnica is irritant, stimulant, depressant; antipyretic, diuretic, diaphoretic and is used as a vulnerary, it dilates the circular blood vessels. It irritates the gastro-intestinal tract. In alcoholic solutions (as tincture of arnica) it inflames the skin when used full strength. In small doses it increases the action of the heart, raises arterial tension and stimulates the action of the skin and kidneys. Large doses produce a transient excitement, followed by depressed circulation, respiration and temperature. USES.--It is a very efficient diaphoretic for horses in one or two ounce doses diluted in one pint of water; one-half ounce of fluid extract pilocarpus may be added at the outset of inflammatory diseases of any kind, such as lymphangitis, laminitis, pulmonary diseases, etc. Excellent to stop a chill and prevent the following fever or inflammatory action. It does this by dilating the blood vessels of the skin, thus attracting the blood to the surface and away from congested internal organs. It is indicated in sthetic fever of any kind; azoturia, rheumatism, especially inflammatory or articular; congestion of the brain, kidneys, etc., externally much used, but of little value on hairy animals. ARSENUM--ARSENIC ORIGIN.--The world’s supply of arsenic and arsenic compounds at the present time is obtained from Germany, Spain, England, Canada and portions of the United States, as Montana and Washington, where considerable quantities of arsenic are being produced as a by-product in the smelting of copper ores. Arsenic ore is roasted and purified by sublimation, before it is used for medical purposes. ARSENI TRIOXIDUM--ARSENIC TRIOXIDE ACIDUM ARSENOSUM--ARCENOUS ACID (White Arsenic) DERIVATION.--Arsenical ores are roasted or conducted into condensing chambers and purified by sublimation.