Prunus lauro cerasus Lin. Sp. Pl. 778.

The root of this tree or shrub is large, rough, and furnished with many fibres. The branches are woody, numerous, brown on the outside, and white within. The leaves are large, fleshy, oblong, shining, pointed at both ends, and slightly serrated at the edges: their upper surface is smooth, and of a light dark green colour; the under side is of a light green, rough, strongly marked with fibres. The flowers appear towards the superior part of the branches; are penta-petalous, in five leaved cups, followed by clusters of berries resembling cherries, and containing an oblong stone. It flowers in May, and ripens its fruit in September.

The leaves have a bitter taste, with a flavour resembling that of bitter almonds, or the kernels of peaches and apricots, which is communicated to water and alcohol by infusion or distillation. These preparations are so suddenly deleterious, either in the stomach or rectum, or applied to wounds, as sometimes to occasion instant death. Dr. Mead relates, that a few spoonfuls of laurel water killed a large dog before it could be supposed to have reached the stomach; and it acts by destroying the mobility of the nervous power without exciting inflammation, or producing any sensible change in the state of the fluids. Like all other powerful sedatives, it produces violent spasmodic motions of the whole body; though, when in a concentrated state, it is often immediately fatal without such previous symptoms.

As it evidently lessens or destroys the irritability of the nervous system, increasing at the same time, according to Wurtzer, the action, he thinks it useful in great nervous irritability, particularly where from this cause the heart is affected with palpitations.

On dissection, no uncommon appearances are observed in the stomach or intestines; the arteries are found empty, and the veins turgid with blood. The sinuses of the brain, and the veins of the pia mater, are distended; the effect rather of the convulsions than the particular properties of the poison. Less than two spoonfuls of the first runnings of the simple water of laurel leaves killed, within a short time, a healthy young woman, previously producing violent convulsions. Various have been the speculations respecting the action of this poison. It has been supposed to affect exclusively the vital functions, as it produces death independent of sleep; but the brain is the great source of every power, and we are not yet prepared to say, that different portions of it may be affected, to any considerable degree, without an affection of the whole; or that functions of any kind are connected with a determined part of the organ. The disputes, whether it coagulates or dissolves the blood, are still more trifling; for the extravasations observed are very certainly owing to a loss of tone in the vessels. It has been employed as amedicine in the cure of intermittents; in resolving scirrhous tumours,.and in phthisis pulmonalis; but neither its dose nor its powers are so properly ascertained as to enable us to speak, of it with precision; and its deleterious effects are so striking, as to deter us from even the most cautious trial.

Although the poison of laurel appears to-consist in the essential oil which it affords in distillation, yet it is suspected that an infusion of the leaves is also injurious. Even the flavour communicated in some galenical and culinary processes has been dreaded, though without reason. The mucilage dissolved with the essential oil seems a sufficient guard.

It hath been generally observed, that if the animals that had swallowed this poison vomited it up readily, they recovered; but its action seems too speedy on the human race to hope for relief by any means. See Venenum; Wilmer on Poisonous Vegetables; and Cullen's Materia Medica.