An audience at the U.S. Military Academy hoped to see military relics or historical documents pulled from the box. Instead, they let out a groan after experts pried open the top and pointed a camera inside to show just a layer of sediment on the bottom.

West Point archeologist Paul Hudson and West Point Museum curator Michael Diaz gingerly lifted out a few gray clumps and dusted them with a brush, only to have them crumble into powder.

“A little disappointed. We built up to this quite a bit,” Hudson said after the event. “And I’ll tell you the truth, that was the last outcome that I expected with all the trouble that they went to create that box, put it in the monument.”

The box, which is about a cubic foot, was discovered in May during the restoration of a monument honoring Revolutionary War hero Thaddeus Kosciuszko. That led to speculation there might be items inside honoring Kosciuszko or from cadet life in the late 1820s, when the monument was erected. Would there be any musket balls, messages from students, or clues to historical mysteries?

The underwhelming results of the live opening brought comparisons to Geraldo Rivera’s televised 1986 unsealing of a Chicago hotel vault purportedly belonging to gangster Al Capone, which infamously revealed nothing but dirt. In fact, academy officials joked about the possibility before the official unsealing.

“I was told yesterday that if we had a sense of humor, we would have asked Mr. Rivera to be up here with us,” Brig. Gen. Shane Reeves, the academy’s academic dean, told the crowd of cadets, officers and civilians.

Though they can’t say for sure, Academy officials think the box was left by cadets in 1828 or 1829, when the original monument was completed. A committee of five cadets that included 1829 graduate Robert E. Lee, the future Confederate general, was involved with the dedication of the monument.

Kosciuszko had designed wartime fortifications for the Continental Army at West Point. He died in 1817. A statue of Kosciuszko was added to the monument in 1913.

Hudson said it appeared that moisture seeped in from a damaged seam on the box and it was likely that sediment got inside. The conditions also could have disintegrated any organic matter inside, like paper or wood.

“We’re going to remove all of that sediment and we’ll screen it through some fine mesh screen and see if anything comes out of it,” Hudson said.

Though historians aren’t certain of exactly when the box was placed in the monument, or who put it there, they say a stamp found Monday on the underside of the lid reading “E.W. Bank N.Y.” might provide a clue.