Under this title a combination of antipyrin and chloral— trichloral-dehydphenyl-dimethylpyrazolon—has been introduced. It has so many chemical, physiological, and therapeutical affinities with the remedies now under consideration that it may well be described in this place.

Hypnal is without odor or taste; it occurs in rhombic prisms, and is soluble in water in the proportion of one to five or six parts. It may therefore be given in solution in water, or combined in suitable mixtures. The dose ranges from 10 to 40 grains.

As its composition indicates, hypnal is possessed of hypnotic, analgesic, and antipyretic actions. It has been employed successfully for the relief of insomnia, hemicrania, and other kinds of neuralgia, and to reduce abnormal temperature. Unusual exemption from after ill consequences is claimed for this agent. It is said to cause little or none of the cardiac depression, the profuse sweating, the chills, etc., which attend on the action of its congeners, antipyrin and chloral. When massive doses are given, however, the usual precautions against accident should be taken.

Butyl-hypnal differs from ordinary hypnal in being a combination of antipyrin and butyl-chloral. It has not been much used hitherto.

Hypnone is a hypnotic, and has less pain-relieving power. It is adapted to the same conditions as those in which paraldehyde is now prescribed. Dubois advises the use of hypnone to promote anaesthesia when chloroform is administered. But its chief employment will be confined to the more simple cases of insomnia, we conclude after some investigation of its powers.