Arsenic ( n. ) One of the elements, a solid substance resembling a metal in its physical properties, but in its chemical relations ranking with the nonmetals. It is of a steel-gray color and brilliant luster, though usually dull from tarnish. It is very brittle, and sublimes at 356! Fahrenheit. It is sometimes found native, but usually combined with silver, cobalt, nickel, iron, antimony, or sulphur. Orpiment and realgar are two of its sulphur compounds, the first of which is the true arsenic> Arsenic ( n. ) Arsenious oxide or arsenious anhydride; -- called also arsenious acid, white arsenic, and ratsbane.
The Qanun was translated into Latin as Canon medicinae by Gerard of Cremona . (Confusingly there appear to have been two men called Gerard of Cremona, both translators of Arabic texts into Latin. Ostler states that it was the later of these, also known as Gerard de Sabloneta, who translated the Qanun (and other medical works) into Latin in the 13th century.)  The encyclopaedic content, systematic arrangement, and combination of Galen's medicine with Aristotle's science and philosophy helped the Canon enter European scholastic medicine. Medical scholars started to use the Canon in the 13th century, while university courses implemented the text from the 14th century onwards.  The Canon ' s influence declined in the 16th century as a result of humanists' preference in medicine for ancient Greek and Roman authorities over Arabic authorities, although others defended Avicenna's innovations beyond the original classical texts. It fell out of favour in university syllabi, although it was still being taught as background literature as late as 1715 in Padua.  
"Of course," said the Psychologist, and reassured us. "That's a simple point of psychology. I should have thought of it. It's plain enough, and helps the paradox delightfully. We cannot see it, nor can we appreciate this machine, any more than we can the spoke of a wheel spinning, or a bullet flying through the air. If it is travelling through time fifty times or a hundred times faster than we are, if it gets through a minute while we get through a second, the impression it creates will of course be only one-fiftieth or one-hundredth of what it would make if it were not travelling in time. That's plain enough." He passed his hand through the space in which the machine had been. "You see?" he said, laughing.