Herodotus wrote that it was the practice of the Scythians to inhale the vapors of a certain kind of hemp to produce intoxication. The use of the mandrake plant as an anæsthetic is spoken of as far back as Pliny, the Roman historian. The sleep-producing effects of the mandragora or mandrake are alluded to by Shakespeare. He also frequently mentions in a general way draughts that act as anæsthetics, without making clear their specific natures. An old Chinese manuscript indicates that a physician of that country named Hoa-tho in the third century after Christ used a preparation of hemp as an anæsthetic in surgical operations. Although the ancients had knowledge of anæsthetics of one kind or other, the practice of anæsthesia never became general, and surgeons of the ancient world appear to have looked upon it with disfavor. When in modern times Joseph Priestley, the English scientist (born in 1733, died 1804) gave great impetus to chemical research by his discoveries in that science, the nature of gases and vapors was more and more closely studied. The belief soon sprang up that many gases and vapors would ultimately become of great value in medicine and surgery. In 1800 Sir Humphry Davy experimented with nitrous oxide gas, called "laughing gas," and discovered its anæsthetic qualities. He suggested its use in surgery, but for practically half a century his suggestion passed unheeded. Other scientists experimented with greater or less success, seeking to find something that would alleviate physical pain; but to Dr. William T. G. Morton, an American, belongs the credit for the practical introduction of anæsthetics into modern surgery. Dr. Morton was born in Charlton, Massachusetts, August 9, 1819. His ancestors were of Scotch extraction. He passed his early years in farm work. At the age of thirteen he entered an academy at Oxford, Massachusetts, where he remained only a few months, attending school thereafter at Northfield and Leicester. His father's financial condition caused him to leave school in 1836 and enter the employ of a publishing firm in Boston. Deciding to engage in the practice of dentistry, in 1840 he took a course in the Baltimore College of Dental Surgery. Two years afterward he began the practice of his profession in Boston. As dentistry at that time was in its beginnings as a distinct profession, Dr. Morton took up, in addition to it, the study of general medicine and surgery in the Harvard Medical School.