A time capsule buried in the cornerstone of the Massachusetts statehouse by Samuel Adams and Paul Revere, might have remained hidden forever had it not been for water damage in the building that required structural repairs.

The small copper box dating back to 1795 was discovered by repair workers. They called historians who reported the alleged existence of a box containing memorial items placed into the huge cornerstone by the two Revolutionary-era founders.

The Boston Globe reported that the box was once before discovered amidst emergency repairs to the building in 1855, and was returned to its spot following the construction, remaining unopened.

Based on historical records, the box is believed to contain coins, a plate and a plaque inscribed by Revere, who was a silversmith — but no one knows for sure.

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