“Life depends on compromise.” So said Theresa May soon after she began her long, dogged, uninspiring defence of her deal.

How despondent her little band of supporters looked. The Chief Whip’s hair seems thinner every time he enters the chamber. Pained sympathy was the dominant expression on their faces.

They admire her unflagging industry and courage, but sense that she is neither eloquent enough nor sufficiently fertile in expedient to win back the supporters who are deserting the Government.

Stuart McDonald, a Scottish Nationalist, remarked that it “feels like the fall of the ancien regime”, and that was indeed how it felt. One had the sensation that power is seeping away from  this administration, and that the votes it lost this afternoon just demonstrated something which had already begun.

The Prime Minister strove to frame the choice facing the House: “This deal, no deal, or the risk of no Brexit.” MPs must support her deal because anything else would without question be worse.

And for a long time she strove to sell the Northern Ireland backstop. Conor Burns (Con, Bournemouth West) rose, remarked that he comes from the Province and as “a Catholic and a Unionist” understands it pretty well, and asked why her view of the backstop is “not shared by those who understand Northern Ireland the best”.

Lady Hermon (North Down), a former Ulster Unionist who now sits as an independent Unionist, sprang to May’s defence,  declaring from a position just behind Nigel Dodds, the parliamentary leader of the Democratic Unionist Party: “The DUP do not speak for the majority in Northern Ireland.”

She turned with spirit on the Labour benches and reproached them: “I’m sorry that people think this is funny. It’s really serious for the people of Northern Ireland.”

It’s really serious for May too. Hermon is alone, but Dodds commands ten votes, which provided her with a majority, and which are no longer at her disposal. “It’s what’s in the legal text that matters,” Dodds said, and it was clear from his white, intransigent expression that as far as the Prime Minister is concerned, the DUP is pretty much a lost cause.

Yvette Cooper (Lab, Normanton, Pontefract and Castleford) told the Prime Minister that “by over-claiming what is in the Political Declaration she is undermining trust”, and asked her to “be straight with the Parliament and the country about the Political Declaration”.

This was damaging, because May did indeed seem to be bending her deal a bit in order to make it look a bit better. She dared not risk the generous candour about its defects shown the previous day by the Attorney General.

And some of us recalled how, as Home Secretary, May walked all over her Labour opponent, who for a time was Cooper.

George Freeman (Con, Mid Norfolk) wondered whether, “as she confronts the inevitable contradictions” of this process, May has “considered a free vote”.

Ah yes, a free vote as used by Edward Heath when he was taking the United Kingdom into the Common Market, so  that Labour rebels led by Roy Jenkins would find it easier to lend him their indispensable support.

Perhaps May can pull off something similar, but one cannot say she looks as formidable as Heath did when he was taking Britain in, for he plainly believed in what he was doing, whereas she just looks as if she is engaged, albeit with the utmost conscientiousness, in a damage limitation exercise.

Two senior Conservative backbenchers, Dominic Grieve and Sir Oliver Letwin, had earlier spoken in favour of an amendment which if May’s deal fails, and by 21st January no agreement has been reached, will enable the majority in the House of Commons which opposes a no deal Brexit to take control and avert that outcome.

In the early stages of a revolution, there are usually some members of the establishment who believe they know how to steady the ship.

Letwin said that in his view, leaving without a deal would be “a catastrophe for our country”, and the aim was to ensure “the right to crystallise and express” the majority in the House against such an option should the need arise.

Hilary Benn (Lab, Leeds Central) rose to express his agreement: “It is essential” – what heartfelt emphasis he gave to the word “essential” – “that the House of Commons has the opportunity to give itself a voice to express a view about what happens next.”

Andrea Leadsom, for the Government, spoke against the Grieve/Letwin amendment, but it was passed by 321 votes to 299. A coalition of centrist MPs is getting ready to take over if May is seen definitively to have failed. It may not have long to wait.