Prices on the London Stock Exchange rose Thursday as players crept back into the market to pick up marked-down shares after Wednesday's rout. The Financial Times-Stock Exchange 100-stock index was up 15.5 points, or 0.9 percent, at 1,772.3 at the close. On Wednesday, the index fell 35.8 points. Trading volume was a modest 340.8 million shares, compared with Wednesday's 575.5 million shares. Traders said the market was attempting to consolidate after Wednesday's fall. The positive showing in Tokyo and Wall Street's better opening Thursday also supported London equity prices, dealers said. ``People have discounted Wednesday's performance because they realize it was overdone,'' one equity salesman said. In addition, the market was heartened by some favorable corporate earnings reports, dealers said.