(1) A treatise on food and drink, dedicated to Mamun. (2) An introduction to logic. (3) Extracts from medical Pandects. (4) A book on fumigatories. Isa bin Musa, who flourished about A.D. 833, was also one of the most distinguished physicians of the period. He left the following works: (1) Book on the forces of alimentary substances. (2) A treatise for a person who has no access to a physician. (3) Questions concerning derivations and races. (4) Book of dreams, indicating why medicines should not be given to pregnant women. (5) Book of the remedies mentioned by Hippocrates in his treatise on bleeding and cupping. (6) Dissertation on the use of baths. Without giving any details about Maseweih, Yahya bin Maseweih, Honein bin Ishak, and Kosta bin Luka, all of whom were distinguished for medical knowledge, some fuller mention must be made of Abu Bakr Ar-Razi (Rhases), who has been described as 'the ablest physician of that age and the most distinguished; a perfect master of the art of medicine, skilled in its practice, and thoroughly grounded in its principles and rules.' He composed a number of useful works on medicine, and some of his sayings have been handed down to us, and are still worthy of record, such as: (1) When you can cure by a regimen, avoid having recourse to medicine. (2) When you can effect a cure with a simple medicine, avoid employing a compound one. (3) With a learned physician and an obedient patient sickness soon disappears. (4) Treat an incipient malady with remedies which will not prostrate the strength. Till the end of his life he continued at the head of his profession, finally lost his sight, and died in A.D. 923. A new and much improved edition of Razi's 'Treatise on the Small-Pox and Measles' was published in London in A.D. 1848 by Dr. Greenhill, and an article on him will also be found in Wuestenfeld's 'History of the Arabian Physicians.' Poetry flourished to a very great extent during the reigns of the early Abbaside Khalifs, and, as all Arab _litterateurs_ were more or less poets and writers of verses, it is somewhat difficult to select the most celebrated. The first collection of Arabic poems was compiled by Al-Mofadhdhal in the work called after him--'Mofadhdhaliat.' He was followed by Abu Amr as Shaibani, by Abu Zaid bin A'us, Ibn-as Sikkit, Muhammad bin Habib, Abu Hatim es Sejastani, and Abu Othman al Mazini. Abu Tammam and Al-Bohtori, the collectors of the two Hamasas, are considered to be the two greatest poets of the third century of the Hijrah (A.D. 816-913). And it may here be observed that in the great bibliographical dictionary of Haji Khalfa, who enumerates seven Hamasas, the names of Ibn-ul Marzaban and of Ibn Demash, each of whom composed one, are not mentioned.