The Sensex at the Bombay Stock Exchange surged 197 points, or 1.1 percent, to cross the 19,000-point mark, at 19,013, in afternoon deals, a few minutes ago, amid continued buying by foreign funds and retail investors, on expectations of better fourth quarter corporate results. Earlier, in the morning, the Sensex had opened 90 points higher, at 18,905. The benchmark index has already rallied more than 975 points in the last four trading sessions.But stock markets in Japan,South Korea, Singapore, Hong Kong, Taiwan and Indonesia were down by between 0.1 percent and 0.8 percent, on Monday.