WITH investor sentiment quickly sinking, the only positive sign in the market yesterday was the Hang Seng Index snapping a string of six consecutive declines by rising a modest 3.51 points to 6,956.1. But volume of only $3.02 billion provided further confirmation that the summer doldrums had taken root after an exciting first half of the year. Smith New Court broker Simon Caplow said many foreign institutional investors were taking a cautious approach until they assessed China's troubled economic situation, while local investors were waiting to see how Shanghai Petrochemical's public offer would turn out. ''Everyone is looking for the right entry point and volume tells you everyone's on the sidelines,'' he said. ''There's not a lot of news out there.'' Seapower Securities research director Samuel Lau Kwok-leung said the market was sluggish and investor sentiment was poor, especially among retail investors. ''They don't want to get into the market because there's no stock they can punt,'' he said, adding that the market would remain dull until there was a breakthrough on the political front. One of few interesting developments was Harbour Centre Development, which fell 14.2 per cent or $1.40 to $8.40 after Wharf Holdings called off plans to privatise the company. Wharf abandoned the attempt because it failed to win enough support from minority shareholders for its $10.50 a share offer, which was launched in April. Schroder Securities issued a research report yesterday saying the aborted deal would be negative for Harbour Centre's shares because Wharf was not allowed to make another privatisation bid for a year. It recommended investors sell Harbour Centre stock at above $7.80, at which level it would sport a price-earnings ratio of 15 times based on 1993 earnings of 50.8 cents a share. Schroder said the $1.2 billion raised by Wharf for the privatisation would be used for other investment and it continued to rate the stock, which dipped 10 cents to $19.90, a buy. Guoco Group fell 40 cents to $20.40 after confirming on Monday that it was one of the parties in discussion with the Government about Overseas Trust Bank. Cheung Kong was the most heavily traded stock with turnover of $196.8 million. The stock fell 50 cents to an intra-day low of $25.60. It has tumbled 6.9 per cent since July 2 when it hit $27.50, just off its high of $28. Mr Lau said Cheung Kong's decline was puzzling, adding that further weakness was likely because there appeared to be little support at lower levels. Hutchison Whampoa lost 10 cents to $20.30 on turnover of $192.3 million as bargain-hunters continued to pick up stock. Among the other blue-chip counters, Jardine Matheson fell $1 for the second consecutive day to $56.50 while Hongkong Land gained 10 cents after dropping recently. Lei Shing Hong posted the day's biggest gain, jumping 25.4 per cent or $1.175 to $5.80. Brokers said the stock was thinly traded so any buy or sell order could dramatically affect its price. Last month, Lei Shing Hong announced a $421 million rights issue to finance expansion in China. It also unveiled a two-for-three bonus share issue. Giordano Holdings was down 15 cents to $4.15 but only after recovering from a drop to $3.80 earlier in the day. Brokers said the price fell because a large sell order was placed in the morning. Fortei Holdings and Egana International, which both listed on the stock market recently, posted gains. Fortei was up 5.5 per cent or eight cents to $1.53 while Egana rose 8.3 per cent or seven cents to 91 cents. International Semi-Tech Microelectronics said yesterday that chairman and principal shareholder James Ting would acquire 1.16 million class B multiple voting shares in exchange for 1.29 million class A subordinate voting shares in a series of private agreements.