Still another of these Arabian Christians, who acquired a reputation as writers in medicine, was Alkindus. He wrote with regard to nearly everything, however, and so came to be called the philosopher. He is said altogether to have written and translated about two hundred works, of which twenty-two treat of medicine. He was a contemporary of Honein Ben Ischak in the ninth century. Another of the great ninth-century Christian physicians and translators from the Greek was Kostaben Luka. He was of Greek origin, but lived in Armenia and made translations from Greek into Arabic. Nearly all of these men took not alone medical science, but the whole round of physical science, for their special subject. A typical example in the ninth century was Abuhassan Ben Korra, many of whose family during succeeding generations attracted attention as scholars. He became the astronomer and physician of the Caliph Motadhid. His translations in medical literature were mainly excerpts from Hippocrates and Galen meant for popular use. These Christian translators, thoroughly scientific as far as their times permitted them to be, were wonderfully industrious in their work as translators, great teachers in every sense of the word, and they are the men who formed the traditions on which the greater Arabian physicians from Rhazes onward were educated. It would be easy to think that these men, occupied so much with translations, and intent on the re-introduction of Greek medicine, might have depended very little on their own observations, and been very impractical. All that is needed to counteract any such false impression, however, is to know something definite about their books. Gurlt, in his "History of Surgery," has some quotations from Serapion the elder, who is often quoted by Rhazes. In the treatment of hemorrhoids Serapion advises ligature and insists that they must be tied with a silk thread or with some other strong thread, and then relief will come. He says some people burn them _medicinis acutis_ (touching with acids, as some do even yet), and some incise them with a knife. He prefers the ligature, however. He calmly discusses the removal of stones from the kidney by incision of the pelvis of the kidney through an opening in the loin. He considers the operation very dangerous, however, but seems to think the removal of a stone from the bladder a rather simple procedure. His description of the technique of the use of a catheter and of a stylet with it, and apparently also of a guide for it in difficult cases, is extremely interesting. He suggests the opening of the bladder in the median line, midway between the scrotum and the anus, and the placing of a canula therein, so as to permit drainage until healing occurs.