However much the Foreign Secretary assured them that the "dreaded F-word" was nowhere to be seen in papers for the 1996 conference on the future of the union, the so-called Fresh Start group clung to their scepticism.
In a series of interventions they advocated the repatriation of powers to nation states, staying out of a single currency and clipping the wings of the European Court of Justice.
"Federalism may not be spelt out literally but is in action the whole time through the Court of Justice," Iain Duncan-Smith, MP for Chingford, said.
Citing the stable currency and living standards of Switzerland, Bernard Jenkin, MP for Colchester North, said: "Life outside the EU need not necessarily mean death." And few Tories wanted to leave the union - they wanted to "redefine" Britain's relationship with it.
Sir Teddy Taylor, MP for Southend East, said Europe was "going down the plughole economically and politically". Britain should seek relations with countries which believed in free trade "and nothing else".
But Edwina Currie, Tory MP for Derbyshire South, warned that no anti- European party had ever been elected in this Britain. "The voters, for all their grumbles, know on which side their bread is buttered. I should like to hear words of hope and enthusiasm from this Government over Europe and not the nit-picking and criticisms which have become too many ministers' stock in trade."
With his customary sang-froid, Mr Hurd sought to assure sceptics that the European "mind-set" had changed and no one in authority now talked of a United States of Europe. Only the Labour Party had failed to notice what was going on, he said.
"They now embrace the ideas of the Eighties just when the debate in Europe is moving on." They clung obstinately to the Social Chapter and the minimum wage when the accent was on restoring Europe's competitiveness, not undermining it further.
"To those Conservative MPs who quite understandably and rightly want to establish clear blue water between the views of the Opposition and the views of the Government on Europe, I would simply say this: you have it."
He urged them to read Tony Blair's speeches and those of the Prime Minister. "We do not need to retreat into a string of negatives or a mood of sourness in order to establish a difference between the parties. The difference exists."
Differences also exist between Mr Hurd's memory of Baroness Thatcher's approach to Europe when prime minister and how she recalled it last week when branding Mr Major a "Yes, yes" man.
"She challenged the assumptions of the day with a great deal of vigour. She now summarises her stance as `No, no no'. My own recollection is rather of `No, maybe, yes'." That had been her approach to negotiating the British rebate, to the "decisive extension" of majority voting in the Single European Act, and would also have been her approach to Maastricht, he said.
Intervening, Sir Edward Heath, the former Conservative Prime Minister, said it was an "immense reassurance" that ministers would follow the technique of "saying `no, no, no', and then `yes' and signing up".
Unable to resist a dig at Mr Hurd as his "former assistant", Sir Edward went on: "If ministers follow that excellent example we shall get the things Mr Hurd has been describing and those niggling behind us [the sceptics] will be defeated and we shall all share the benefits."
Lady Thatcher's attempts to distance herself from the Single European Act were also mocked by Robin Cook, who said it was as if "she thought it had been an agreement with Singapore ... nobody had told her that the end-user would be the European Commission".
Conservative MPs joined in the laughter, but they had occasion to squirm as Mr Cook exploited the party's divisions on Europe. Noting that Mr Major had penned the forewords of both Euro-scpetical and Euro-positive pamphlets, he advised the party to hold on to the Prime Minister. "He seems to be the only person in the party who can possibly span the gulf they are opening up between themselves over Europe."
Mr Cook said Labour did not support a federal Europe or a superstate. "We favour an EU which is a free association of independent member states, not surrendering sovereignty, but sharing a common interest." He accused Tories of retreating "into the rhetoric and mindset of an 18th century nation state".
Intervening, Hugh Dykes, the Tory Europhile MP for Harrow East, said: "The Government is facing increasingly dotty xenophobia and a manic dislike of socialism in Christian Democrat Germany, for instance, by members of my party. This is going to get worse." In a novel move, he urged Labour to agree to free votes on Europe in the Commons, "where there is a large built-in majority for European developments" - perhaps in return for the abandonment of controversial plans like rail privatisation.
After urging Mr Dykes to have a word with the Labour chief whip, Mr Cook returned to his thesis. "Tories are limbering themselves up to fight the next election as the nationalist party of Britain," the Labour spokesman said. He would be very happy to fight the election against a party that would rather retreat to the 18th century - and he had no doubt which century the electorate would choose.
For the Liberal Democrats, Charles Kennedy said it would be better the Tories split over Europe rather than remain divided within one party. The Government was caught in the headlights of its backbenchers, immobilised between pro- Europeans and Euro-sceptics.