Polymer manufacturer Victrex was the highest riser on the FTSE 250 index by the close of trading in Tuesday with its share price having jumped nearly nine per cent to 1,769p after its first-half results.Victrex posted modest growth in revenues and volumes in the first six months of its fiscal year, though a slight fall in profits still came in ahead of expectations. The company boosted its interim dividend by 15% year-on-year to 10.35 per share, well ahead of analysts' forecasts for a 4-5% increase. Soft drinks maker AG Barr edged higher as it managed to increase revenues by 2.4% in the first quarter in spite of the dismal weather. HICL Infrastructure Company was among the fallers after the infrastructure projects investor announced that it had completed two investments worth a combined £41.6m, taking the number of investments in its portfolio to 85. FTSE 250 - RisersVictrex (VCT) 1,769.00p +8.66%Telecity Group (TCY) 995.00p +5.57%Ashtead Group (AHT) 665.00p +4.97%International Personal Finance (IPF) 554.00p +4.92%Spirax-Sarco Engineering (SPX) 2,911.00p +4.45%Supergroup (SGP) 788.00p +4.44%Persimmon (PSN) 1,272.00p +4.26%Brewin Dolphin Holdings (BRW) 219.50p +4.18%Cable & Wireless Communications (CWC) 45.83p +4.16%New World Resources A Shares (NWR) 109.90p +3.88%FTSE 250 - FallersEnQuest (ENQ) 130.60p -1.95%Hochschild Mining (HOC) 242.50p -1.94%FirstGroup (FGP) 125.00p -1.88%Heritage Oil (HOIL) 149.40p -1.71%African Barrick Gold (ABG) 128.10p -1.69%Rank Group (RNK) 144.10p -1.44%HICL Infrastructure Company Ltd (HICL) 128.30p -1.31%Salamander Energy (SMDR) 165.00p -1.08%Devro (DVO) 335.40p -1.06%Kenmare Resources (KMR) 31.33p -1.04%MF