Between him and Galen an interval of some six hundred years elapsed and, especially in the latter half of that period, pharmacy developed into enormous importance. Not that it necessarily advanced. But the faith in drugs, and especially in the art of compounding them, and the wild polypharmacy which grew up in Alexandria and Rome in the first two centuries of our era, of which Galen shows so much approval, add inestimably to the chronicles of pharmacy. It was during the interval between Hippocrates and Galen that the many sects of ancient medicine, the Dogmatics, the Stoics, the Empirics, the Methodics, and the Eclectics were born and flourished. Some of these encouraged the administration of special remedies. But probably a far greater influence was exercised on the pharmacy of the ancient world by the new commerce with Africa and the East which the Ptolemies did so much to foster, and by the travelling quacks and the prescribing druggists who exploited the drugs of foreign origin which now came into the market. Serapion of Alexandria, one of the most famous of the Empirics, who is supposed to have lived in the second century, was largely responsible for the introduction of the animal remedies which were to figure so prominently in the pharmacy of the succeeding seventeen centuries. Among his specifics were the brain of a camel, the excrements of the crocodile, the heart of the hare, the blood of the tortoise, and the testicles of the wild boar. The Empirics were the boldest users of drugs, and so far as can be judged, were the practitioners who brought opium into general medicinal esteem. One of the most famous doctors of this sect, Heraclides, made several narcotic compounds which are commended by Galen. One of these formulæ prescribed for cholera was 2 drms. of henbane seeds, 1 drm. of anise, and ½ drm. of opium, made into 30 pills, one for a dose. Another which was recommended for coughs was composed of 4 drms. each of juice of hemlock, juice of henbane, castorum, white pepper, and costus; and 1 drm. each of myrrh and opium. Musa, a freed slave of Augustus, and apparently a sort of medical charlatan, but a great favourite with the Emperor, is alleged to have introduced the flesh of vipers into medical use especially for the cure of ulcers. Celsus, Dioscorides, and Pliny, whose works are recognized as the storehouses of the science of Imperial Rome, belonged to the period under review. Celsus wrote either a little before or a little after the commencement of our era. He was the first eminent author who wrote on medicine in Latin. Pliny died A.D. 79, suffocated by the gases from Vesuvius, which in his eagerness to observe he had approached too near during an eruption. Dioscorides is supposed to have lived a little before Pliny, who apparently quotes him, but curiously never mentions his name, though usually most scrupulous in regard to his authorities.