In presenting the Seventh Edition of the "Dental Medicine," the author entertains the hope that his labors have resulted in such an improvement of this work as to render the present edition more valuable than the one that preceded it.

The success which has attended the issue of the different editions has been very gratifying, and its popularity has been shown by the short time which has elapsed between them.

The number of opportunities thus offered to revise its editions have been taken advantage of to increase its usefulness as a textbook for dental students, and also as a reference book for dental practitioners.

The advance of Dental Materia Medica and Therapeutics has been such as to render it necessary to increase the size of this work in every revision, in order that it may fulfil the object of its preparation; hence, among the remedial agents, and combinations of such agents which have been added to the present edition are the following : Vapocaine, Chloretone, Enzymol, Eu-formal, Phenalgin, Airol, Actol, Glucide, Glutol, Orthoform, Caffein, Digitalis, Sozoiodol, Liquid Air, Nitrous Oxide and Oxygen, Nitrous Oxide and Atmospheric Air, Pressure Anaesthesia by compressed Air, Sulpho-Carbolate of Zinc, Silver Sul-pho-Carbolate, Anestile, The Treatment of Dental Caries with Nitrate of Silver, The Hypodermic Syringe, etc., etc. A new Table of Doses of Medicinal Agents has been substituted for the one in former editions.

Important additions have been made to many articles such as those on Inflammation, Diagnosis and Treatment of Mouth Affections, embracing Abscess, Ulceration, Caries and Necrosis of Bone, Gangrene, Septicemia, Pyemia, Opening Abscesses, Erosion of Teeth, Stomatitis, Sterilizing Instruments, Administering Anaesthetic Agents, both Local and General; together with important additions, including recent investigations on the physiological and medicinal actions and properties, and Therapeutic and Dental Uses of many of the remedies, including anaesthetics, before noticed in this work.

Ferdinand J. S. Gorgas. Hamilton Terrace, Baltimore, Md.