ACTION AND USES.--Linseed oil cannot be used as a diet on account of its being too laxative; it is laxative in small doses, but in large doses produces copious discharges of faeces, having a distinct linseed oil smell. The oil is also emollient, soothing and softening to inflamed and indurated surfaces. As a laxative it usually produces tolerably full and softened evacuations, without nausea, griping or superpurgation and with decided odor of oil. It is the best physic to administer to pregnant animals and in irritable conditions of the bowels; also in cases of influenza, purpura and other debilitating diseases, where the usual purgatives would be too severe, irritating and exhausting. It is also used as an enema; two to four ounces of the oil or meal given daily in mash often suffices to maintain the bowels in a relaxed condition throughout febrile attacks, where there is a tendency to constipation. An ounce or two of oil given daily often relieves broken wind in horses. For burns and scalds the well known _carron oil_, composed of equal parts of linseed oil and lime water, cannot be surpassed. This oil is also used as a vehicle for acrid medicines and to act as a protective to the alimentary tract in poisoning of corrosive medicines, also to sweep them out. Carron oil in two to four ounce doses two to three times daily will often relieve “heaves” in horses. Linseed oil is frequently given to ruminants, although Epsom salts is generally the best purge for them. It is indicated for these animals when a milder operation than that obtained by a full dose of salts is required, and for its demulcent action in irritable states of the digestive organs. MAGNESII SULPHAS--MAGNESIUM SULPHATE--EPSOM SALTS DERIVATION.--Magnesium sulphate is a constituent of sea water and of some saline springs. It also occurs native, either crystallized in slender, prismatic, adhering crystals, or as an efflorescence on certain rocks and soils which contain magnesia and a sulphate or sulphide. In the United States it is found in the great caves so numerous to the west of the Alleghany Mountains. PROPERTIES.--Small, colorless, rhombic prisms, or acicular crystals, without color and having a cooling, saline and bitter taste; slowly efflorescent in dry air; .85 part of water; insoluble in alcohol.