ever, as a department of philosophy. The disciples of Pythagoras, who had become physicians, are stated to have been the first to introduce the custom of visiting the sick at their own homes. They also went from city to city, hence they have been called Periodeutæ, i.e., periodic ambulant or itinerary physicians. The Asclepiada were consulted by the sick in the temples and treated there. Anaxagoras (b. 499 B.C.), the friend of Perikles and Euripides, used the term νους as representing mind and an intelligent principle. Empedocles (b. 490-430) formulated and extended the view of the constitution of the organic beings as consisting of fire, air, earth, and water. He dwelt upon the importance of heat. He is said to have foreshadowed the doctrine of the struggle for existence. Democritus (b. 494-460, d. 391) was a contemporary of Socrates. He acknowledged the distinction between mind and body. He considered. that both consisted of atoms differing in their qualities and arrangement. From his speculations there necessarily arose the doctrine of the immortality of the soul. To Democritus atoms were indestructible, and as both body or mind or soul were composed of atoms, the soul was necessarily eternal or immortal.

The Asclepiads were a sort of medical guild or close corporation transmitting their knowledge and secrets from generation to generation, and formed a professional class quite apart from the priests. The three most famous schools where temples were erected were those of Cnidos, Rhodes, and Cos. Perhaps Cos is the most celebrated. It produced many famous disciples of medicine, and of these the most celebrated was Hippocrates the Second. In fact the oldest written monument of the Greek art of healing is the famous Hippocratic oath. At Cos in 460 B.C. was born this same Hippocrates, the "Father of Medicine," who was regarded as a direct descendant of Asclepios. He was a few years older than Plato, and younger than Socrates. He lived in the age when Perikles was the most prominent figure in Greece, and when he was striving to make Athens the queen of the Hellenes at a time when poetry was represented by Pindar, Euripides, Sophocles, Eschylus, Aristophanes; the earliest historians represented by Thucydides, Xenophon, and Herodotus; the earliest and greatest dramatists by Aristophanes and Eschylus; the greatest philosophers by Plato and Socrates; and sculpture by Phidias.

The Parthenon was finished in 438 B.C. The temples of Athens in all their magnificence and grandeur were the direct outcome of the Persian invasion. The Mede had been defeated, and it behoved the grateful Athenians to pay their debt of gratitude to Heaven for the great victory vouchsafed to them. Perikles saw the importance of carrying out a great scheme worthy of the gods, for by ennobling the houses of the gods Athens ennobled herself. Thus Athens expressed her gratitude, her might, and her intellect in the construction of beautiful temples. The pressing claim was the completion of the Temple of Athena-Polias or Parthenon on the Acropolis, which had been begun in the days of Themistocles. This perfect Dorian temple contained the statue of Athena wrought in the style called Chryselephantine, i.e., a wooden statue covered with gold and ivory and designed and wrought by the genius who gave his name to the plastic art of the Periklean age, Phidias, the son of Charmides.

Hippocrates gave medicine an independent existence and freed physiology, such as it was, from the airy speculations of the natural philosophers. He relied upon observation and experience, and was a most accurate observer. Still he explained but little. Disease was not sent by the gods, but was due to natural causes. Necessarily this view of the matter changed the whole method of treatment. He proved himself a philosopher by setting up one uniform cause, viz., the doctrine of pvous or nature, as it were one divinity or person that maintained the even course of events whereby man's health was maintained. Disturbances resulted in disease. We have here foreshadowed the "vis medicatrix naturæ." The body was regarded as composed of fire, air, earth, and water; it had four humours, blood, phlegm, black and yellow bile, and these in proper proportions represented the condition of health. The blood was formed in the liver and coagulated outside the body, and when it was beaten it yielded fibres. The epiglottis obstructed the passage of food into the lungs. The cause of life was the innate heat which is formed in the heart. Respiration moderated the heat in the lungs, and especially of the heart. The reverence of the Greeks for the dead prevented a knowledge of anatomy being acquired directly from the dissection of the dead body.

Let me recall the fact that the works of Hippocrates were translated into English for the Sydenham Society by a Scottish surgeon the learned Francis Adams, LL.D., surgeon-who resided in a small country village, Banchory, in Aberdeenshire (1849). Adams claims for Hippocrates a very considerable knowledge of anatomy. Even to Hippocrates, however, there was no distinction between the white nerves and the white tendons. The nerves conveyed the animal spirits through the body, while the blood vessels contained blood and pneuma. The brain, the largest of the glands, secreted pituita or mucus, and therefore it was not the centre of intelligence and the reasoning faculties. The Hippocratic period concludes the first stage in the history of medicine and physiology. So far there was no independent physiology. Speculations without a basis of observation and experiment characterise the whole period, and, indeed, there could be no real physiology until an accurate anatomical substratum existed. The views of the Greeks regarding the sanctity of the dead prevented them from adopting one of the great means by which such knowledge can be acquired. We know but little of the personal history of Hippocrates. He received his education at the Asclepion of Cos under his father, Heraclides, and at Athens he studied under the hygienist, Herodicus, of Selymbria. He travelled much in the cities of Thrace and Macedonia, but he tarried longest in Larissa and other cities of Thessaly, where he is said to have ended his days. He moved from place to place, and therefore is classed with the periodeutæ or ambulant physicians. According to Celsus he taught medicine as a distinct department of practical knowledge. Pliny regards him as the first to give clinical instruction, using for that purpose the votive tablets of the temples. We must remember that Hippocrates lived in stirring times, and times of great progress, and it is not surprising that the healing art should, like the sister arts, find a genius to systematise the knowledge already available, to add to it by his own labours and observation, and to give the whole a scientific value. These books of Hippocrates revealed to the world what had been taught only to the initiated. From Cnidos had been promulgated the "Cnidian sentences." Thucydides in the history of the Peleponesian war gives an account

of the plague of Athens with which there is nothing to compare in any of the treatises of Hippocrates. Hippocrates at that time was about thirty years of age. Thucydides refers directly to the

spread of this disease by infection.

The second period in the history is marked by the work of Aristotle (b. 334 at Stagyra, in Macedon). He was a disciple of Plato at Athens. When he was over forty he was summoned by Philip of Macedon, to be tutor to Alexander. Aristotle may be said to be the founder of comparative anatomy and comparative physiology. His royal patron and pupil secured for him an immense collection of natural products and all manner of animals for observation and dissection. Moreover, he also obtained for him a valuable library which ultimately found its way to Alexandria. Plato in his academy, and Aristotle in his lyceum, were the originators of two diverse and opposite schools of philosophy, the one holding that all our knowledge is derived from mental intuition, the other that all our ideas are due to impressions made on the senses. In his famous axiom, "All ideas come from the senses," Aristotle laid the basis of empiricism.

In the treatise on analysis we read: "It appears that all animals have received from nature, the faculty of sensation and judgment; but after a sensation has been produced some preserve the remembrance of it and others do not. Those who retain no reminiscence of the impressions have no idea of the things beyond immediate sensations. Those, on the contrary, whose soul retains some traces of past sensations can, at the end of a great number of such, reason from the recollection which they keep of them. In this way the memory comes from the faculty of feeling. The remembrance of a thing often repeated creates experience, and experience, that is to say, every general notion which becomes fixed in the soul, relative to the common properties of certain things, abstraction made from their differences this notion, I say, is the principle of science and art." Although Aristotle was the first of the sentients, he soon departed from this, his first axiom, and in his physiological speculations he did not begin with the study of elementary facts. He boldly proceeds to discuss the nature of the soul, its faculties and its functions. The soul is the essence of all things living, vegetable and animal alike. It has

four faculties, nutritive or vegetable, sensitive peculiar to animals, motive, and intellectual. The seat of the last is not the brain, but the heart. He gives a fairly accurate, broad description of the brain, although he had no idea of its uses. The great work of Aristotle, "De Animalibus Historiæ," is divided into nine books. It is plain that the spirit of inquiry had already outgrown and extended beyond the confines of the temples. The practitioners of the healing heart were separated from the votaries of the priesthood. Already there were apothecaries, physicians, and medical philosophers. Aristotle put together a system of physiology which lasted nearly two thousand years. All vital phenomena were due to the natural or innate heat which belonged to the blood, and the central focus thereof was the beating heart, from which proceeded pulsating vessels which supplied the parts with blood, like water to a garden. Blood nourished the organs and gave them mobility and sensibility. Blood is formed from the food digested in the stomach. It is changed by "pepsis" into chyle. The heat of the heart keeps the blood fluid. The useless parts of the food are removed by the intestine and kidneys. The sense organs are placed in the head to protect them from the excessive heat of the heart. He discovered the "punctum saliens" in the incubating

egg.

(To be Continued.)