After President Obama took his first oath and he and guests cleared the Capitol balcony, government curators walked on to the empty platform to begin collecting various items they’d previously marked for keeping as historical artifacts.

Everything was accounted for — except the water glass set out for the president. That was inexplicably missing.

“I remember specifically thinking, I can’t believe someone took that. How inappropriate is that?” Diane Skvarla, the Senate’s then-curator, said. She retired in January 2014.

For almost seven years, she had no idea what happened to that glass. That is, until last week when she read about Rep. Bob Brady (D-Pa.) swiping Pope Francis’s water glass from the House chamber. And his boast that he’d also taken a glass from Obama’s 2009 swearing-in ceremony.

Here at the Loop we joked Monday that Brady had saved the pope’s glass from being sent through a dishwasher and back to a random cupboard. That might still have been true. The House curator, Farar Elliott, in an e-mail said, “While the House Curator’s office collects numerous documents and artifacts from events that occur in the U.S. House to preserve for posterity, it has not been a practice to accession House drinking glasses into the House Collection.”

But Skvarla, who held the job in the Senate for 20 years, believes the two glasses should have been curated.

“I guess I became a little bit angry since this was something we clearly had planned to collect and I never knew where it had gone,” Skvarla said of the Obama glass. “Well, now I know where it is. Can anything be done about it? I hope (Brady) would recognize these two pieces are important to the history of our country.”

The collection of Capitol artifacts began in the late-1960s after Senate Majority Leader Mike Mansfield, in a 1965 floor speech, said, “Congress has a responsibility to see to it that they are passed along unscathed and undiminished. These … historic items belong to all generations of Americans, past, present and future. Their preservation is a responsibility which cannot be taken lightly, for once marred, lost or destroyed they can never be replaced.”

Most people don’t know this exists. When we called Brady’s office to ask if he’d consider returning the glasses, a senior staffer didn’t seem to know about the curator offices. Skvarla said the office intentionally keeps a low profile due to the sensitive nature of preserving and protecting the artifacts.

It’s all so secretive that she said viewing the items, or the temperature-controlled rooms where they are stored, is not an option for the public or the press. (We asked for a tour.)

After Bill Clinton’s impeachment trial, the curators went onto the Senate floor and saved the name plates and the pencil used by the clerk to tally votes. More recently, a curator saved a rubber band ball that had sat by the Speaker’s chair for years, growing larger and larger, until someone decided it was a distraction. They arranged with the caterers to keep dishes, glasses and silverware from Obama’s first inaugural luncheon.

“As a curator our job is to look ahead, what will be interesting in 200 years?” Skvarla said.

Brady’s office never got back to us on whether he’d consider giving the glasses back. Skvarla is hopeful that Brady will see the historical importance and hand them over.

But, she said, “He can keep the water.”

No matter what he decides, Brady’s conscience seems to be cleared. As we reported Monday, Brady was prepared to pay the House Clerk the $3.94 he was billed for the glass.

And, when he met Pope Francis on the tarmac upon his arrival in Philadelphia, the congressman confessed to taking his glass and the water left in it. Brady told the Philadelphia Daily News that the pontiff responded, Bueno, bueno” and added in English, “Good, give it to the people who are sick and the babies.” (He says he has.)

So, now that the mystery of the Obama inaugural water glass is solved, we have to wonder, what other random items have gone missing?