Opticks

About this book

Opticks, published in 1704 and written in English rather than Latin, describes Isaac Newton's experiments with light: passing sunlight through prisms to show that white light is a mixture of colours, measuring how each colour bends, explaining the rainbow and the coloured rings that appear between two pieces of glass. The book ends with a series of open questions about light, matter and gravity.

Context and significance

Newton delayed the book until after the death of his rival Robert Hooke. Its method of patient experiment made it a model for science, and it continued a tradition that goes back to the Arab scholar Ibn al-Haytham, whose Book of Optics had transformed the study of light seven centuries earlier.

About the author

Isaac Newton (1643–1727) was born on a farm in Lincolnshire and studied at Cambridge. When the plague closed the university in 1665, he went home and, in about two years, laid the foundations of calculus, of his theory of light and colour and of the idea of universal gravitation.

His Principia of 1687 explained the movements of the planets and the tides with the same laws that govern a falling apple, and Opticks showed that white light is made of colours. Later in life he ran the Royal Mint, chasing counterfeiters, and presided over the Royal Society, while privately studying alchemy and theology.