In addition to recommending a number of gemstone amulets against the plague, he gave detailed instructions on how to make the putrid toad-vomit treatment, according to two unpublished pages handwritten by Newton that are now on the auction block.
Newton describes in detail how to suspend a toad by its legs in a chimney for three days, until it vomits up “earth with various insects in it.” This vomit must be caught on “a dish of yellow wax,” he added.
After the toad dies, its body should be turned into powder, mixed with the vomit and a serum and “made into lozenges and worn about the affected area.” This treatment would drive “away the contagion” and draw “out the poison,” Newton wrote.
The toad treatment was best, but if someone was in a pinch, then amulets made out of the gemstones hyacinth, sapphire or amber could also serve as antidotes, he wrote.
Newton and his contemporaries didn’t know that the plague doesn’t respond to toad vomit or gems. It wasn’t until 1894 that the French-Swiss scientist Alexandre Yersin learned that the disease is caused by a bacterium, which was later named Yersinia pestis in his honor.
These days, plague is treated with antibiotics, not vomit from toads that were hung upside down. (On a somewhat related note, if you want to see a toad throw up, here’s a video.)
Newton likely wrote these notes on the plague shortly after returning to the University of Cambridge in England in 1667, according to Bonhams, the auction house selling off the documents. The plague had just swept through Europe, forcing the University of Cambridge to temporarily close its doors in 1665. During that time, Newton quarantined at Woolsthorpe-by-Colsterworth, a hamlet in Lincolnshire, England, where he investigated the laws of gravity and motion. The year 1666 became known as his “annus mirabilis,” Latin for “wonderful year.”
However, while the polymath’s laws of motion became blockbusters, his writings on the plague’s causes, symptoms and treatments did not enjoy world renown. In truth, these notes weren’t entirely his own. Rather, Newton had been reading “Tumulus Pestis” (“The Tomb of the Plague”), by Jan Baptist Van Helmont, a chemist, physiologist and physician from the Spanish Netherlands, a collection of Holy Roman Empire states also run by the Spanish Crown.
“Newton’s notes are not verbatim transcriptions of Van Helmont’s text, but rather a synthesis of his central ideas and observations through Newton’s eyes,” according to Bonhams.
Not everything Van Helmont wrote was dismissed by later generations. For instance, he found that chemical reactions could produce substances that were neither solids nor liquids, which led him to invent the word “gas,” according to the Science History Institute in Philadelphia. But religious zeal led to some unusual medical treatments. A verse in the King James Bible at time proclaimed “the Lord created medicines from the earth, and a sensible man will not despise them,” (Ecclesiasticus 38:4). Van Helmont interpreted this line to mean that doctors were ordained by God, and spent the rest of his life convincing others that this was his role, according to the Science History Institute.
In 1936, Newton’s “plague” manuscript was sold along with a vast trove of his other writings in Sotheby’s Portsmouth sale, but these two pages were uncovered only recently after being lost for more than 70 years, according to Bonhams. Bidding is currently at $65,000 and goes until June 10.
Originally published on Live Science.