Active Ingredients. - In England the bay tree is immediately distinguished from all other out-door evergreens by the cinnamon odor of the bruised leaves. This proceeds from a volatile oil, contained also in the fruit. The latter holds in addition a fixed fatty oil, and other ingredients. The "oil-of-bays" of commerce, oleum lauri expressum, which is a compound of the volatile oil and of the fixed fatty oil, is obtained from the drupes, whether fresh or dried, by means of heat and pressure.

Physiological Action. - The volatile oil obtained by distillation of the berries with water is aromatic, stimulant, and narcotic. In large doses the leaves are emetic.

Therapeutic Action. - Both the leaves and the fruit of the bay tree have been employed to strengthen the digestive organs; also to prevent flatus. They are also said to act as an emmenagogue.

The oil obtained from the fruit is employed externally as a stimulating liniment in cases of sprain and bruises. It has likewise been given in paralysis, and has been employed for the relief of colic, and to mitigate deafness; but these uses are now obsolete.

The fruits enter into the composition of the emplastrum cumini.