The Sensex at the Bombay Stock Exchange was trading 50 points in positive territory at 18,515 a short while ago. Earlier Sensex rose by 218 points in early trade today. The 30-share barometer, which had gained over 1,153 points in the previous eight sessions, shot up further by 218 points to 18,682.In a similar fashion, the wide-based National Stock Exchange index Nifty moved up by 19 points to 5,596.