Not very long after he had returned to Pergamum, Galen was summoned by the Emperors Marcus Aurelius and Lucius Verus, who were then with the army at Aquileia, a few miles north of the present Trieste, to join them at that city; and he was, of course, obliged to obey. A fresh outbreak of the Plague had occurred and there had already been many fatal cases among the troops. It was therefore decided by the emperors, almost immediately after Galen’s arrival, to return to Rome with a part of the army. A start was accordingly made, and the company had already advanced some distance on their way, when Lucius Verus died. This unexpected event greatly increased the difficulties of the return journey, as it was deemed necessary to carry the remains of the deceased Emperor back to the imperial city. Thus Galen found himself once more settled in Rome, this time in the capacity of private physician to the Emperor Marcus Aurelius and his sons Commodus and Sextus. The position was extremely well adapted to the needs of Galen, who, from that time forward, for a period of several years, had at his disposal ample time for writing and for conducting his experimental work in anatomy and physiology, a privilege of which he appears to have made excellent use. He lived to be seventy years of age, his death occurring during the latter part of the reign of Severus, or at the beginning of that of Caracalla (about 201 A. D.). All Galen’s critics agree that he possessed his full share of peculiarities,--not to call them by the harsher name of faults. He was constantly ready, for example, to praise his own doings and sayings, and he rarely lost an opportunity of holding up the physicians of Rome to ridicule and contempt. He was specially bitter in his criticisms of Methodism and its adherents--“the donkeys of Thessalus,” as he called them. At the same time, no other physician of ancient or modern times has manifested to an equal degree such extraordinary industry as a writer and original investigator in a great variety of departments of knowledge. Although many of his works have been lost,[39] those which have come down to our time are still very numerous--“a sufficient number,” says Neuburger, “to constitute a library by themselves.” I give here a few of the titles of these works, in order that the reader may get at least some idea of the great variety of medical topics which Galen has discussed in his writings. The more complete list furnished by Daniel Le Clerc contains nearly two hundred titles, and yet even this is believed to fall short of the actual number. SELECTED LIST OF THE WORKS OF GALEN RELATING TO MEDICINE. (FROM LE CLERC.) Explanation of some of the Ancient Terms Employed by Hippocrates. On the Establishment of the Art of Medicine. Definitions of Medical Terms. On the Different Sects in Medicine. Discourse against the Empirics.