Edme Mariotte and Newton’s Cradle

The first recorded experiments describing the phenomena made popular by Newton’s cradle appear to be those conducted by Edme Mariotte around 1670. He was quoted in Newton’s Principia, along with Wren, Wallis and Huygens as having conducted pioneering experiments on the collisions of pendulum balls. Each of these authors concluded that momentum (then described as the “quantity of motion”) is conserved when one ball collides with another. Mariotte’s collision experiments were presented to the French Academy of Sciences in 1671 and subsequently published in 1673 as “Traité de la percussion ou choc des corps ”. The treatise was included in a larger volume of his work, titled “Oeuvres de Mr Mariotte”, published by the Academy in 1717, describing his discovery of the blind spot in the eye and the relation between pressure and volume for gases, as well as many other studies on plants, planets, strength of materials and fluid mechanics. 1-3 Newton was inadvertently credited with the modern version of the executive toy that bears his name, and it is still being described as “Newton’s cradle ” even by physicists4. It is interesting to read the original account of the experiments conducted by Mariotte and his explanations of the effects observed. Unfortunately, the original 17th Century French treatise appears not to have been translated into English. Mariotte’s short account of his ball chain experiments is translated here by the author into a slightly modernised English version in the interests of clarity. Figures 17 and 18 referred to in the text are those published in the 1717 edition of Mariotte’s work. That edition can be found in rare book collections, and is also available digitally on line (pages 66 to 68 are translated below) a