David DiLaura, professor emeritus at the University of Colorado, was working on his extensive bibliography of all major science books on optics when he made an unexpected discovery. The copy of Isaac Newton’s seminal treatise optics which he had purchased some 20 years earlier turned out to be from Newton’s own personal library, thought to have been lost for decades. The book will go on sale at the Rare Books San Francisco Fair, February 3-5, 2023, with a price of $375,000.
“It’s becoming increasingly rare for a private copy of a book of this size to remain under the radar for years,” said Pom Harrington, owner of Peter Harrington Rare Books, who is handling the sale. When DiLaura purchased this copy from an English rare book dealer in West Sussex more than 20 years ago, neither the buyer nor the seller had any idea of its history. DiLaura has described his discovery as “a once-in-a-lifetime lifetime event’.’, and it is. Rare book collectors and dealers love a good story of rediscovery, especially one that came to light – quite literally in this case – the way this one did .’
Newton is rightly most famous for his principle and the co-invention of calculus, but he also had a long-standing interest in optics. For example, he once inserted a long sewing needle (bodkin) into his eye socket between eye and bone and recorded the colored circles and other visual effects he saw. And as a young scientist at the University of Cambridge, he conducted what is known as his experimental cross, who darkened his room on a sunny day and made a hole in the shutter to let a narrow beam of sunlight into the room. He then placed a glass prism in the sunbeam and observed the rainbow bands of light in the color spectrum.
When he placed a second prism upside down in front of the first, the color band recombined into white sunlight, proving his hypothesis that white light consists of all the colors of the combined spectrum. Based on his color theory, Newton concluded that refracting telescope lenses would be plagued by chromatic aberrations (the scattering of light into colors) and built the first practical reflecting telescope, using reflecting mirrors instead of lenses with the aim of solving that problem . In 1671 he gave a demonstration of his telescope to the Royal Society.
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Newton was also at the center of a heated debate over whether light was a particle or a wave – a debate that has raged for millennia. For example, Pythagoras was staunchly “pro-particle,” while contemporaries ridiculed Aristotle for daring to suggest that light propagates like a wave. Empirical observations of the behavior of light contradicted each other. On one side, light traveled in a straight line and bounced off a reflective surface. This is how particles behave. But it can also diffuse outward, and different rays of light can cross and mix. That’s wave-like behavior.
By the 17th century, many scientists had widely accepted the wave nature of light, but there were still detractors in the research community — including Newton, who vehemently argued that light was made up of streams of particles he called “corpuscles.” In 1672 colleagues persuaded Newton to publish his conclusions on the corpuscular nature of light in the Royal Society’s Philosophical Transactions. He seemed to expect his ideas to be met with unanimous acclaim and was offended when Robert Hooke and the Dutch physicist Christiaan Huygens criticized his conclusions.
All these insights and more eventually formed the basis of Newton’s last treatise, opticsfirst published in 1704. At the time, English astronomer John Flamsteed stated that it “makes no noise in the city”, unlike when principle was published. But it still represented an important contribution to optical science, alongside that of Johannes Kepler Astronomia Pars Optica and Huygens’ Traite de la Lumiere. Also different than principle, optics is written in English instead of Latin, which makes it much more readable.
