New warnings from software and networking firms triggeredsubstantial new losses Tuesday, with an absence of buyers indicatinggrowing revulsion for U.S. shares. The Nasdaq Composite fell 109.97to 1673.00 or 6.1 percent to its lowest since October 1998. Thetechnology-heavy composite has fallen 30 percent this year and is 66percent off its high of last year, far more than other major averages.The Dow Industrials fell 292.22 on Tuesday, or 2.9 percent, to9485.71. The Dow is down 12 percent for the year. "There's fear,investors are throwing in the towel," said Michael Lyons, seniordealer at Morgan Stanley Dean Witter.