more dogmatic doctors who were not happy unless they could understand the ratio of men's bodies and of their disturbances. They professed a rational medicine and held it necessary to understand the antecedent and obscure, as well as the palpable, causes of the disease, and insisted upon a knowledge of anatomy. In their opinion those who best knew the constitution of the body and the causes of disease had the best chance to effect a cure. Experience was important, but must always be approached through the ratio of things.

Then Celsus speaks of those who adhered to the methodum, the simple but sufficient way, which was in fine a rather Roman simplification of Greek theory, especially of the atomic theory and its application to the constitution and diseases of the human body. In general -and the Methodists preferred generalizations to the specific knowledge which was more difficult diseases are due to a condition of undue tension or rigidity in the body, or on the other hand to excessive relaxation. In the first case, the pores between the atoms are clogged, and in the second they are too loose and open.

The theory was elastic and the treatment reasonable, consisting in warm baths

and other relaxing or invigorating measures as the case seemed to require.

Expressing his own opinion, Celsus decides for a middle course, whereby medicine should rely upon experience rationally: let one treat the evident causes of the disease, and as for the remote, meditate on them. Students should learn anatomy from the bodies of the dead and from study of living and wounded men. The surgical portions of Celsus's handbook are particularly good.

Theories sat rather lightly on these excellent practitioners of the Greco-Roman time, who might call themselves by one name or another. This remark applies to members of the socalled "Pneumatic" School, who were generally eclectic, adopting the best features of medical practice in the second half of the first century. They were affected by the Stoic physics, in which borrowed materials filled out a system novel in form. Accepting the old working elements, they found the life-giving principle to be the "Pneuma," like unto air and breath. It is innate, yet constantly renewed through breathing, and circulates with the blood through the arteries and veins to all parts of the body, the arteries conveying

more pneuma, and the veins more blood. Pneuma vivifies the body, and makes it a living unity, carries on the energies of growth and reproduction, as well as of sensation, desire, and thought. The normal condition and proper Tovos or tension of the pneuma means health, and this is indicated by the pulse; while sickness springs from disorder of the pneuma, due to irregularities of the warm and cold or dry and moist elements, and the consequent morbid excess of one or the other of the humors.

While these "Pneumatics" rejected the fundamental theory of the Methodists, they availed themselves of their treatment of disease, and drew upon all the best medical knowledge of the time. They were wise physicians, following many a precept of Hippocrates, and efficient surgeons. One among them, Archigenes, a contemporary of Trajan, seems to have been extraordinarily resourceful and inventive: "what we need is to be fertile in expedients, not to be always attending to the writings of other people," said he.

Says Sir Clifford Allbutt: "The ancient Greeks shrank from mutilation; and amputation, mentioned by the Hippocratean physi

cians only in gangrene as a subsidiary aid, seems, even in Alexandria, to have made no great progress; for Celsus also regarded it as a last sad resource in gangrene: yet by the time of Trajan, under Archigenes, amputation had become a recognized procedure for ulcers, growths, injuries and even deformities. The limb to be removed was bandaged to expel the blood, and a tourniquet was placed above the line of severance; or sometimes the chief blood-vessels were first cut down and tied, and the smaller tied or twisted, during the operation-transfixing them with a sharp hook and twisting them round and round and closing them by this twisting' a proceeding of which there is no trace in Hippocrates, nor apparently in the earlier Alexandria. These good methods were afterwards obliterated by the bad fashion of the searing-iron." 63

From the side of philosophy as well as physiology, it is interesting to note how the Pneumatic School represents a stage in the mind's search for a vital principle to account for the living man, and more specifically to account for the animal heat, which is a clearly vital quality, and yet indicative of ill whenever it rises above a certain degree, as in

fevers, or whenever it falls below, as at the approach of death. From Homer downward, the breath of man suggested itself as the vital principle or its vehicle. How about its relation to the body's heat? This perplexing question brought great confusion.6* Air seems both hot and cold; and any one can blow hot or cold with the same mouth. Was the vital and necessary breathing of the air, in and out, a cooling or a warming of the body? Opinions wavered and contradicted each other for centuries. Apparently the whole matter is exceedingly obscure the early physicists with Hippocrates were ranged on the side of warming, and Aristotle with his great influence on the cooling side. Nearly two thousand years later, Harvey remained perplexed. After his death, the search was carried on more vigorously for some needed and explanatory process analogous to the burning of combustible things, in fine, for a process of combustion. The goal was reached through the discovery of oxygen and the slow-won knowledge of its functions in the human economy.