John Dalton, F. R. S. (1766-1844) and the Atomic Theory—A lecture to commemorate his bicentenary

Abstract

We have met today to honour the memory of John Dalton who was born two centuries ago. He was elected into the Royal Society in 1822 and was awarded the first Royal Medal in 1826. Dalton’s name is always associated with Lavoisier’s in my mind as the two men who made nineteenth century chemistry possible. There could be no greater contrast than their circumstances: Lavoisier with all the advantages of education and opportunity that wealth could give; Dalton, the son of a weaver, earned his living by teaching from the age of twelve. Meteorology was the first scientific interest of both, an interest that they maintained throughout their lives. Neither had the superb qualitative perception of Priestley or Scheele, both relied on measurement, both were striving after fundamental causes. Lavoisier worked in a great laboratory with fine instruments, Dalton with home-made apparatus, in early days in his own room, like Davy and Berzelius. The approach of both was from the physical rather than the chemical side. Lavoisier in a moment of elation at the start of his study of gases, following on his first experiments on combustion, set down his conviction that his work was destined to accomplish a revolution in chemistry and physics. Dalton gave his book the proud title—A New System of Chemical Philosophy. Both their claims were amply justified by subsequent events.