The insomnia that attends excessive fatigue may be very quickly relieved by the use of food and alcohol. For this purpose any form of alcoholic drink will be found useful. The quantity administered should only be sufficient to produce a uniform and general vascular relaxation. By this means the circulation is equalized throughout the body, and the brain passes into a state of tranquil sleep. Any excess in the use of alcohol under such conditions will be followed by headache and discomfort on awaking. In all cases the intoxicating dose of alcohol must be avoided, if its truly hypnotic effect be desired. _Paraldehyde._--This is a derivative from ethyl alcohol. It is, when pure, a colorless liquid, with an agreeable odor, somewhat like that of ether. It is soluble in the proportion of one part in eight or nine of water. It may be used internally in doses varying from forty-five to one hundred and sixty grains. A watery solution, containing one part to ten, has been recommended for internal administration. It may also be given in milk or in beer. M. Yvon[43] recommends the following formula: Paraldehyde, Gr. 20.0 Spirit, 100.0 Syr. Simpl., 75.0 Tr. Vanillæ, 5.0 An ounce of this mixture contains forty-five grains of paraldehyde. When taken it should be still further diluted with sweetened water, or with beer, to obviate, as far as possible, the disagreeable taste of the drug. Sleep follows after the lapse of about half an hour, and continues from five to seven hours. The physiological action of the medicine is very similar to that of chloral hydrate, and its use is indicated in the same class of cases to which that drug is appropriate. By many it is considered the preferable hypnotic. It has found considerable employment in the insane asylums of Europe, and in other institutions where disagreeable medication is no obstacle to experiment. In private practice the peculiar taste and smell of the article, and its pungent effect upon the mucous membranes of the alimentary canal, render its exhibition more difficult. But the weight of testimony is in its favor as an hypnotic in all cases, uncomplicated with disease of the stomach, in which insomnia is not dependent upon pain, and is associated with cerebral hyperæmia. Its administration is followed by no unpleasant consequences. Among the insane it is particularly recommended during periods of excitement and wakefulness. It has been employed with great satisfaction[44] in cases of insomnia during the course of such varied diseases as emphysema, bronchitis, phthisis, nervous and spinal disorders, diseases of the heart, jaundice, chronic rheumatism, and insomnia from other unrecognized causes. Undoubtedly, with greater skill in its purification and exhibition, it will become one of the most valuable of hypnotic remedies. Almost useless for the relief of pain, it is indicated in cases of uncomplicated insomnia.