Early Discoverers XXXI: Descartes’ Observations on the Amsterdam Snowfalls of 4, 5, 6 and 9 February 1635

Abstract

In Les météores (1637), in the midst of a father far-fetched theory of their origin, Descartes incorporated a detailed description, from actual observation, of a variety or kinds of snow crystals and hail particles. These even include the tsuzumi crystals, described as “wheels joined two by two by an axle” or as “little crystal columns decorated at each end with a six-petalled rose”, and such exceptional forms as twelve-rayed and eight-rayed stars. The accompanying diagrams, which have been reproduced a number of times, are distinctly inferior to his verbal description.