The Anglo-Swedish alliance took time to excite. Hopes of lower interest rates continued to make much of the running but by late afternoon blue chips were on a drugs-inspired high with Footsie, up 76 points, nudging 5,700. A little profit taking near the close left the index with a 53.4 plus at 5,669.1.
Zeneca, at one time up 253p, ended with a 191p gain at 2,711p. Trading was again feverish with Seaq turnover almost 22 million shares.
The possibility of more merger activity in the pharmaceutical industry and another drugs group barging into the cosy Astra/Zeneca deal helped pump the adrenaline.
SmithKline Beecham, which had high-profile but abortive merger talks with Glaxo Wellcome earlier this year, rose 33p (after 53p) to 790p and Glaxo, often mentioned as a likely bidder for Zeneca, improved 18p to 1,956p.
Shell, meeting analysts next week, rose 12.5p to 362p as stories swirled that the Anglo-Dutch oil giant could be involved in merger talks with the Chevron oil group.
Rentokil Initial, the environmental group with predatory instincts, rose 24.75p to 405.75p, and Colt Telecom, expected to respond to Tuesday's telecoms merger with a deal of its own, dialled a 32p gain to yet another peak, 872p.
Other Footsie bid favourites such as Vodafone, 33p to 913p, and Bank of Scotland, 15.5p to 688.5p, joined in the fun.
Sears, the retailer where high-street entrepreneur Philip Green hovers, jumped 32p to 270.5p; Rank, the leisure group, rose 11.5p to 224p and Aegis, the media buyer, 5p to 89.75p. Even the bewhiskered old faithful United Biscuits was dusted down for another whirl, up 6.5p to 242.5p.
But Kingfisher, reflecting relief over its trading statement, topped the Footsie leader board with a 61p jump to a 604p peak, a remarkable performance for a retailer in the current spending gloom. Heal's, the furniture chain, rose 25p to 122.5p on its upbeat trading performance but the furniture chain DFS slid to a new low of 157.5p following cautious comments.
ScottishPower, which has felt the weight of market unease over its bid for the US PacifiCorp utility, recovered 22p to 629p, largely on the feeling that its US acquisition could be snatched away by a counter-offer.
The Footsie changes were much as expected. Two constituents of the dismantled Hanson empire, Imperial Tobacco and the Hanson building materials group, have joined the exclusive club; so have the Gallaher tobacco group and Dixons, the electrical retailer enjoying the distinction of being an Internet play.
Out, after only a brief acquaintance with the club, go computer groups Misys and Sema, health care group Nycomed Amersham and old stager British Land.
The mid cap changes dump some famous old names. Joining the small companies index are Booker, the cash and carry chain, MFI, the furniture retailer and Coats Viyella.
Before their relegation was known British Land, caught by the property malaise, was down 28.5p to 450p, a year's low, and Nycomed 8.5p at 355p.
Elsewhere British Aerospace, 21.5p to 525.5p, and Rolls-Royce, 9.25p to 239.75p, flew higher partly on new aircraft orders. BAe was also helped by suggestions that its deal with DaimlerChrysler Aerospace will be concluded today.
Railtrack was shunted backwards on the report of rail regulator Chris Bolt, losing 64p to 1,457p, and indications that Ladbroke is having difficulty achieving the forced sale of its Coral betting shops chain knocked the shares 9.5p to 217p. Stanley Leisure, one contender, has dropped out of the running.
Arriva, the former Cowie transport group, reversed 69.5p to 372.5p following its surprise decision to hang on to its finance division. It said none of the offers it had received reached its valuation.
Takeover activity on the undercard included insurance group Ockham, up 6.5p to 74.5p, bidding for control of insurer New London Capital, 17.5p harder at 84.5p; Zergo, an IT group, 60p higher to 355p on talks with Dublin-based Baltimore Technologies; and property developer City Site, 5p stronger to 32.5p as Miller Group pressed ahead with its 35p offer.
Blockley, the building materials group, held at 41.5p as bidder Natural Building Materials, claiming the backing of shareholders with 40.8 per cent of the shares, continued to attack the defending board. Hewetson, where a possible bidder has made contact, jumped 25p to 175p.
SEAQ VOLUME: 919 million
SEAQ TRADES: 65,848
GILT INDEX: 114.80 +0.46
CHIROSCIENCE could be a casualty of the Zeneca/Astra alliance. The shares plunged 31p to 272.5p as it became apparent its close association with Zeneca could be over. Much of its value relates to its marketing deal with Zeneca for its local anaesthetic. The drugs giant planned to take the treatment through the regulatory process and market it. But Astra has a similar product and Chiroscience is likely to be abandoned.
MORE STAKE BUILDING at Norcor, the packaging group which has for long looked a takeover candidate. The shares held at 49p as Linpac, a packaging rival, lifted its shareholding to 20.36 per cent, buying 1.2 million shares. Jefferson Smurfit, the Irish packaging giant, already sits on a near 30 per cent interest. Norcor's profits are under pressure and the shares are a long way from the 138p peak, hit in 1995.