Occasional use was made by Ó Cuinn of the Liber dietarum particularium which was written by Ysaac Israeli (or Isaac Iudaeus) who lived in Egypt and who died in Tunis about the middle of the tenth century. Ysaac, otherwise Ishaq ibn Amran al-Isra'eli, is said by his Latin translator to have been the ‘adoptive son’ of Solomon, king of the Arabs. He was one of the first of the distinguished Jews who were prominent in spreading Arabic science, especially medicine, to the Western Arabic territories. He was trained as a physician in Baghdad, where he studied Greek medicine and was in touch with the work done there in the translation and exposition of the Greek authorities. Some of his references to Galen are carried by Ó Cuinn into his own text. About the year 900, Ysaac was court physician and philosopher to Ziyadet Allah III at Qairawan, near Tunis. His treatise on urine is regarded as the best medieval work on the subject. Ysaac's