Chloral is usually administered by the mouth in doses, for adults, of twenty to thirty grains, dissolved in sweetened peppermint water. If the first dose does not procure sleep, it may be followed at the expiration of an hour by a second dose of twenty grains. This seldom fails to induce refreshing sleep. When the medicine cannot be tolerated by the stomach it may be given by enema in milk. For this purpose a drachm of chloral should be suspended with the white of an egg in half a teacupful of milk. _Butylchloral hydrate._--This substance has been recommended as a substitute for chloral hydrate, in cases of cardiac weakness, on account of its being less powerful to depress the action of the heart. It is principally useful for the relief of facial neuralgia and hemicrania. As an hypnotic it is seldom used. For this purpose it may be given in a solution like that of chloral hydrate. For a simple anodyne effect the medicine may be given in five-grain doses, repeated every half hour or hour. As a means of procuring sleep it may be given in doses ranging from fifteen to forty-five grains. Liebreich has given the medicine in drachm doses, and recommended it as an hypnotic superior to chloral hydrate. It is useful in the sleeplessness of headaches, neuralgia, dysmenorrhœa, and chronic phthisis. _Amyl nitrite._--This drug has been recommended for the relief of insomnia resulting from the opium habit. Ringer considers it useful in the flushes of heat and other forms of discomfort which sometimes interfere with the sleep of women during the change of life. It should be inhaled in the form of vapor, from a handkerchief upon which five drops have been poured. The quantity will need to be gradually increased, as the system becomes tolerant of its effects. The stimulant effect of the medicine renders its use in this manner probably less dangerous than the similar employment of chloroform. Unlike the other anæsthetics above mentioned, it causes a hyperæmic condition of the brain, and is, for this reason, a useful hypnotic in cases of aortic obstruction with an insufficient cerebral circulation and consequent wakefulness.