Ewart, Peter

Watt to Peter Ewart, 27 February 1814, extracted in Muirhead, Origin and Progress, pp. 346-7. 

When Dalton invented the idea of atoms as participants in chemical reactions, he had the problem of how to stick atomic models together. He instmcted his friend, Peter Ewart, to prepare a set of wooden balls, drill holes into the balls and insert wooden pegs to hold the model in place. These models appeared around 1810, about the same time that Wollaston was postulating the structuring of atoms into regular shapes to form molecules, the word first... 

The mathematical demonstration which Gough asked for was later given by Dalton s pupil Peter Ewart (Troquaire Manse, Dumfriesshire, 14 May 1767-Woolwich, 15 September 1842), a civil engineer, later owner of a cotton-mill in Manchester, and finally Inspector of the Royal Dockyards, Woolwich. 

This argument is reproduced by William Henry, and was provided with a detailed proof based on Newton by Peter Ewart. William Higgins s ideas (see p. 743) seem to me to be different, since they are based mainly on the weakening of the attractive force due to its subdivision on the successive addition of particles to one particle of an attracting element. 

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