Active Ingredients. - The albumen of the seeds yields to boiling water an inodorous and almost tasteless mucilage. By expression the kernels (or cotyledons) yield a bland, inodorous, and sweetish oil, the specific gravity of which is .939. It is much more soluble in alcohol than olive-oil, and, as it is one of the "drying oils," after proper preparation it loses the original unctuousness. Linseed-oil is not congealed except by a cold below 0° of Fahrenheit, and boils at 600° of the same scale.

The seeds, before being submitted to any process, contain about one-fifth of mucilage and one-sixth of oil. (In some qualities of seed the proportion of oil is much larger.) When the oil has been expressed, the refuse is used for fattening cattle, under the name of "oil-cake."

Physiological Action. - Linseed is emollient and demulcent, and the oil is a mild laxative. It has been thought available for human food; but when used as an article of diet, it relaxes the digestive organs, and produces a viscid, slimy mucus, and a morbid acid in the primae viae. These effects may be obviated by the addition of bitter extractive. Linseed, in any case, affords but little nourishment, and is found to impair the stomach, as long ago noticed by Galen. (This does not agree with the recent observations of Sherwell (Trans. Am. Dermatological Assoc, 1878), who found both the whole and the ground seed nutritious, and not a disturber of digestion.)

Therapeutic Action. - When it can be obtained good, - that is to say, as the result of simple expression, as ordered by the Pharmacopoeia, instead of by means of heat, which gives it a disagreeable taste and smell, - linseed-oil is an excellent corrective of habitual costiveness. If a little tincture of rhubarb be added, the most fastidious stomach will not be discomposed.

Linseed, put to stand for a short time in boiling water, constitutes an admirable poultice.

A decoction of the seeds contains not only the mucilage, but a portion of the oil. Hence it becomes a useful material for injections, when there is abrasion or ulceration of the mucous membrane of the intestines.

The infusion, called "linseed-tea," is, for the same reason, a valuable drink for persons who are suffering from irritation of the fauces.

Linseed-tea is also much employed for diseases of the urinary organs; but the wisdom of this use may be questioned.

Mixed with lime-water, linseed-oil has always been a favorite application for burns.

(Linseed has been largely used, and with benefit, by Sherwell, in the treatment of certain obstinate cutaneous affections. We have personally confirmed his observations, sometimes using it mixed with wheat-flour, or corn-meal, and made into bread or cakes in the usual way. As linseed contains no starch, we have suggested it as an ingredient in diabetic biscuits. The linseed employed is not the native variety, but that imported from India.)

Preparations and Dose. - Lini Farina, 3 j. - ij. (30. - 60.); Infus. Lini Compos., ad libitum; Linimentum Calcis, external use.