Unbearable tension in Leinster House when the Dáil returned for business on Tuesday.

The ushers were wearing shinpads and loosening up by lifting dumbbells.

The Ceann Comhairle was running on the spot in his office.

Gerry Adams was perusing his poetry collection in search of suitable solidarity tweets.

And then Mary Lou McDonald went and ruined everything by announcing she wasn’t going to beat her way into the Dáil chamber, resume her sit-in and force the ushers to carry her out.

That wouldn’t be fair on them, she concluded.

So instead, Sinn Féin sent a stiff letter of complaint to the Ceann Comhairle, saying he was being very mean to them and they didn’t like it.

Sean Barrett must have taken it badly, because there wasn't a sign of him for most of the week. He didn't appear at Leaders' Questions, he wasn't in the chair for the big water event on Wednesday and Leas-Ceann Comhairle Michael Kitt was at the helm when Mary Lou McDonald recommenced ongoing hostilities with Joan Burton on Thursday.

Perhaps Barrett was indisposed or away on a foreign trip? But no. There were various sightings of him around the House.

An Oireachtas spokesperson tells us that the Ceann Comhairle was busy doing other duties for most of the week.

And there we were, thinking he was being chivalrous to the deputy leader of Sinn Féin by keeping out of her way.

At the moment, the mere sight of Sean Barrett so enflames Mary Lou that she has to sit down. Often for as long as 4½ hours.

Had it been necessary on Tuesday to physically throw her out of the chamber, Deputy McDonald would have become the first TD in 40 years to be forcibly ejected from the Dáil.

That honour remains with the late Billy Fox, the young Fine Gael deputy for Monaghan who was murdered by the IRA in 1974.

Fox was ordered to leave the chamber when he produced rubber bullets and empty CS gas canisters while describing how the British army was blowing craters in Border roads. When he refused to move, the ushers assisted him out.

Leinster House in the 1970s sounds like great fun. Apparently, in two unrelated incidents, Fianna Fáil’s Neil Blaney and Fine Gael’s Gerry l’Estrange tied themselves into their chairs in an effort to thwart the ceann comhairle.

And retired Oireachtas ushers often recall the case of Liam Ahern, a Fianna Fáil TD for Cork North East in the early 1970s.

Ahern, who died in 1974, gained prominence the previous year during a heated Dáil debate about the seizure of IRA arms aboard the MV Claudia.

Fine Gael was in power and government backbenchers taunted Fianna Fáil leader Jack Lynch over his stance on the discovery.

“Are you sorry the boat was caught, Jack?” asked one of them, whereupon Liam Ahern shouted back: “No. It’s more guns we want – bags of guns.”

On another occasion, Ahern was acting the maggot and given his marching orders by the chair. He refused to budge. Ushers made numerous representations, but he rebuffed their polite requests.

When it looked like they were going to have to end the stan-off by dragging him out, a veteran usher stepped forward and whispered something in the deputy’s ear.

Liam Ahern jumped up immediately and raced out the door.

For months afterwards, the usher refused to tell his colleagues what he had said to make the TD leave in such a hurry.

Finally, he told them.

“All I said was: ‘Your wife is in the hall.’ And he was out the door like a shot.”

A little story about Gerry Adams that passed unoticed

An intriguing contribution to the water debate from Labour’s Joe Costello passed unnoticed on Wednesday.

Costello referred to remarks made by socialist TD Paul Murphy who had “described the imprisonment of the Tánaiste for nearly three hours as a peaceful protest when it was, in fact, imprisonment.”

The deputy for Dublin Central then turned his attention to Sinn Féin. “Members might speak to their leader, Gerry Adams, about the time he was imprisoned in the Lower Ormeau Road and how he took the British government to court.

“In the same fashion, he was surrounded by the RUC and the army for a period of time and could not move in any direction. He might tell them the amount of money he got from the crown. I know all about it because I was present and I was a witness in the court as well.”

Adams brought a claim for £10,000 in damages against the RUC two years after an incident on the eve of a Twelfth of July Orange parade in 1996.

He said he was held for four hours on the nationalist Lower Ormeau Road as part of a police “curfew”.

He was later awarded £500 in damages against the RUC.

Bubble, bubble, toil and trouble in the Dáil canteen

There was no getting away from water in Leinster House this week.

Unless you were dining in the members’ restaurant, where the water removed itself.

Patriotically minded TDs and Senators were surprised to see their usual supply of bottled Irish water off the menu. Upon inquiring, they discovered that the brand usually on offer was temporarily unavailable due to a quality-control issue.

It seems that while the rest of the House was in the grip of water mania, the restaurant’s entire stock of the fizzy stuff was taken away as a precautionary measure by the suppliers. Fear of contamination, our politicians discovered, is not just an issue concerning pipes and reservoirs.

When informed of the change, a senior Government TD exclaimed: “I knew there was something wrong. I didn’t get a wink of sleep last night. I blamed it on the water worry, but it never occurred to me that it might have been the stuff I was drinking in here.”

Anyway, they’re on San Pellegrino for the foreseeable future. And the occasional drop of Prosecco.

Meanwhile, the Seanad decided to get involved in the water lark. On Thursday, Fianna Fáil’s Mary White raised the issue of fluoride.

“Despite the fact that numerous scientific reviews have demonstrated that water fluoridation has greatly benefited the dental health of people over the time span of its use, sadly it has consistently been the subject of disinformation and distortion of evidence,” she said.

Mary spoke on the issue at considerable length, prompting the Cathaoirleach, Paddy Burke, to ask if she was calling for a debate.

Indeed she was, indicated Mary, although this didn’t mean she was about to stop talking.

“I have more important points to make.”

“During my research into this matter, I discovered that wedding presents of false teeth were given in the 1950s and 1960s because often a bride’s or a groom’s teeth were in such a bad way.”

It’s a very educational place, the Seanad.

Scariest line from this week in the Dáil?

That would be from Joan Burton, when bravely reliving her recent imprisonment ordeal during Deputy Leaders’ Questions.

Fianna Fáil's Barry Cowen made a brief comment condemning the actions that saw the Tánaiste imprisoned in her car for over two hours by a baying mob and said he hoped there would be no repeat of such events in the future.

Joan thanked him for his remarks and then gave a comprehensive account of what went down in Jobstown. This left little time to address the actual questions Barry had asked about Irish Water.

(Speaking of which, why was a smiling Mattie McGrath walking around with a water meter in a brown envelope on Thursday, showing it to everyone he met?)

Then Mary Lou was obliged to offer similar expressions of disgust at what befell the Tánaiste during her trip to Tallaght.

Joan got another chance to launch into her gripping tale, with more vivid recollections from the back of the car. So she didn’t much change from her questions either.

In fairness, the Tánaiste had been through a terrible ordeal. One can’t blame her for telling her story.

But you could smell the terror in the chamber when Joan turned to the Leas-Ceann Comhairle and uttered the chilling words: “My reply might take slightly longer than usual.”

Michael Kitt lost the power of speech. Deputies fainted. Grown men blubbered like babies. The ushers fled. Journalists ran for the emergency brandy.

Counselling may yet be required.