The Derby plague of 1665 reference article from the English Wikipedia on 24-Apr-2004
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Derby plague of 1665

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During the Great Plague of 1665 towns like Derby became isolated. Trade almost ceased and populations faced possible starvation, as well as a cruel death by infection with the plague.

Trade was carried out by the positioning of Market Stones at various points on roads leading into the towns.

 
The Headless Cross, also known as the Enlarge

The Headless Cross, also known as the "vinegar Stone" or "Plague Stone" at Friar Gate, Derby England

These stones took many forms, here we see one such stone placed at Friar Gate (formerly Nuns Green) at the northern road into Derby (England). This was a medieval headless cross, and also called the "vinegar Stone" because money was deposited in a trough of vinegar in the top of the stone in the belief that the vinegar would disinfect the coins and prevent the spread of the plague.

Plaque commemorating the relocation of the plague stone from Derby Arboretum to Friargate, formerly Nuns GreenEnlarge

Plaque commemorating the relocation of the plague stone from Derby Arboretum to Friargate, formerly Nuns Green