A Delicate Savior: When Venetian Glass Was Believed to Be a Poison Detector

Venetian glass has long been celebrated for its refined artistry, graceful forms, and clarity of its material. What’s more, some have believed that the purity of the glass would resist deadly poisons. In The Power of Poison, currently at the American Museum of Natural History in Manhattan, the history of poison as a natural defense, a murderous weapon, and even a cure is explored in detail.

A diorama of the three Macbeth witches toiling and troubling over a cauldron is placed alongside an exploration of how the Mad Hatter in Alice’s Adventures in Wonderland references the real mental degeneration caused by the mercuric nitrate once used in the hat making process. Live poison frogs are in residence, as are in-person presentations on poisoning topics like a 19th century case of coffee poisoning with arsenic, which in its tasteless white form was popularly known as “inheritance powder.” Curator Mark Siddall in the AMNH Division of Invertebrate Zoology obviously has an enthusiastic curiosity for all the biology and history of the Earth’s most deadly properties.

One area of the exhibition focuses on “poison detectors,” which is where that delicate Venetian glass comes in. For it was believed that goblets and glassware made on the Murano island in Venice would shiver and shatter when poison was poured into them. In this way, if you weren’t wealthy enough to pay someone to taste your food just in case of fatal flavorings, your trusty Venetian glassware would explode in warning.

Before you head to your local antiques dealer to ease your poisoning paranoia, be warned that sadly Venetian glass, no matter how gorgeous, in actuality has no poison detecting properties. But this didn’t mean that the belief it in it was brief, albeit most prevalent in the 16th century. In Lord Byron’s 16th century Venice-set play The Two Foscari published in 1821, a character proclaims:

“Tis said that our Venetian crystal has
Such pure antipathy to poison, as
To burst if aught of venom touches it.”

Perhaps not coincidentally, this was around the time fear of poisoning was high in Italy, with the most famous case being the infamous Lucrezia Borgia. She may or may not have given dinner guests a dash of death with poison hidden in her hollow ring, although it’s now thought these rumors might actually have been spread by people jealous of her power. Yet the prophetic attributes of Venetian glass didn’t end with the House of Borgia. As John W. Weatherford cites in his Crime and Punishment in the England of Shakespeare and Milton, 1570-1640, a surgeon examining a poison victim in Elizabethan times who had been doused with poison in his food by his wife in cahoots with her “landlady confidante,” “found the poison ‘lying around his heart’” and discovered it “by putting it in a Venetian glass. […] The glass broke. The silly pair confessed, and that was that.”

Venetian glass isn’t the only poison detector highlighted in The Power of Poison; there are also opal rings said to go pale at the presence of poison, Malaysian hornbill spoons that would also change color, and amethyst necklaces worn to protect from poison. They are joined by believed poison purifiers such as fossilized shark teeth (believed to be “dragon tongues”) and agate stones. Yet the Venetian glass is one of the more interesting in showing how the idea of manmade artistic perfection could be projected as real power onto an object.

The Power of Poison is on view through August 10 at the American Museum of Natural History (Central Park West and 79th Street, Upper West Side, Manhattan).