Athol Historical Society President Susannah Whipps-Lee said the time capsule — which has yet to be opened — was made from an old glass container that looked like a pickle jar with a rusted metal screw top. It was buried about 150 years ago, she explained, in what is known as the Old Indian Cemetery or Settlers Burial Ground, which has no gravestones.

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The discovery of the 150-year-old time capsule, with possibly 300 historical documents inside it, was made by Athol history teacher Keith Williams. Mr. Williams read about the hidden treasure in a book of the town’s history and contacted officials to help verify the discovery.

Owing to the degradation of the jar and documents inside, they're waiting for experts to come and open it.