_Health Commissioner of New York City; Former President Medical Board, New York Foundling Hospital; Consulting Physician, French Hospital; Attending Physician, St. John's Riverside Hospital, Yonkers; Surgeon to New Croton Aqueduct and other Public Works, to Copper Queen Consolidated Mining Company of Arizona, and Arizona and Southeastern Railroad Hospital; Author of Medical and Climatological Works._ Menstruation AUSTIN FLINT, JR., M.D. _Professor of Obstetrics and Clinical Gynecology, New York University and Bellevue Hospital Medical College; Visiting Physician, Bellevue Hospital; Consulting Obstetrician, New York Maternity Hospital; Attending Physician, Hospital for Ruptured and Crippled, Manhattan Maternity and Emergency Hospitals._ Heart and Blood JOHN BESSNER HUBER, A.M., M.D. _Assistant in Medicine, University and Bellevue Hospital Medical College; Visiting Physician to St. Joseph's Home for Consumptives; Author of "Consumption: Its Relation to Man and His Civilization; Its Prevention and Cure."_ Skin Diseases JAMES C. JOHNSTON, A.B., M.D. _Instructor in Pathology and Chief of Clinic, Department of Dermatology, Cornell University Medical College._ Diseases of Children CHARLES GILMORE KERLEY, M.D. _Professor of Pediatrics, New York Polyclinic Medical School and Hospital; Attending Physician, New York Infant Asylum, Children's Department of Sydenham Hospital, and Babies' Hospital, N. Y.; Consulting Physician, Home for Crippled Children._ Bites and Stings GEORGE GIBIER RAMBAUD, M.D. _President, New York Pasteur Institute._ Headache ALONZO D. ROCKWELL, A.M., M.D. _Former Professor Electro-Therapeutics and Neurology at New York Post-Graduate Medical School; Neurologist and Electro-Therapeutist to the Flushing Hospital; Former Electro-Therapeutist to the Woman's Hospital in the State of New York; Author of Works on Medical and Surgical Uses of Electricity, Nervous Exhaustion (Neurasthenia), etc._ Poisons E. ELLSWORTH SMITH, M.D. _Pathologist, St. John's Hospital, Yonkers; Somerset Hospital, Somerville, N. J.; Trinity Hospital, St. Bartholomew's Clinic, and the New York West Side German Dispensary._ Catarrh SAMUEL WOOD THURBER, M.D. _Chief of Clinic and Instructor in Laryngology, Columbia University; Laryngologist to the Orphan's Home and Hospital._ Care of Infants HERBERT B. WILCOX, M.D. _Assistant in Diseases of Children, Columbia University._ Special Contributors Food Adulteration S. JOSEPHINE BAKER, M.D. _Medical Inspector, New York City Department of Health._ Pure Water Supply WILLIAM PAUL GERHARD, C.E. _Consulting Engineer for Sanitary Works; Member of American Public Health Association; Member, American Society Mechanical Engineers; Corresponding Member of American Institute of Architects, etc.; Author of "House Drainage," etc._ Care of Food JANET MCKENZIE HILL _Editor, Boston Cooking School Magazine._ Nerves and Outdoor Life S. WEIR MITCHELL, M.D., LL.D.