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Al-Razi, a medical encyclopedist of the ninth century, was an authority on contagion. Among his many volumes of medical surveys, perhaps the most famous is the Kitab al-Mansuri. It was used in Europe until the sixteenth century. Al-Razi was the first to diagnose smallpox and measles, to associate these diseases and others with human contamination and contagion, to introduce such remedies as mercurial ointment, and to use animal gut for sutures.