In 600 B.C. in present-day Israel, a soldier named Hananyahu sent his friend a request that many of us might empathize with: Send more wine.

He wrote his message on a piece of pottery that archaeologists found in 1965. For years, biblical scholars and researchers have studied the front side of the ink-inscribed pottery shard, known as an ostracon, which was commonly used to write receipts, lists or even letters.

They deciphered the Hebrew words about money and Yahweh, which the man had sent to his friend Elyashiv, but it wasn’t until recently that they came across an appeal for alcohol written on the back side. That’s because for nearly 50 years archaeologists thought the back of the ostracon was blank, when really the ink was invisible.