ing in the city, and afterwards as a private tutor of science and mathematics. "As a schoolmaster he began life, as a schoolmaster he ended it," but such routine work was not the sole occupation of his mind—far from it.
His scientific Observations upon the Weather were begun on 24th March 1787, and continued until the day before his death (i.e. for over half a century).
In 1794 Dalton was elected a member of the Literary and Philosophical Society of Manchester, and for fifty years he spent his time, in a room of the Society's house in George Street, in teaching, writing, and studying.
His first paper, in 1794, was "Extraordinary Facts relating to the Vision of Colours." Dalton had a defective colour sense, which was amusingly confirmed by the presentation to his mother of a pair of scarlet silk stockings when he was under the impression that they were drab. On another occasion, when selecting cloth for a new suit of clothes, he requested a drab material; a piece caught his eye, and he remarked that it was just what he required, but the tailor informed him it was scarlet cloth for hunting coats.
About this time he published a book on Meteorological Observations and Essays, recording the connection between the aurora borealis and electricity, on the dew-point, thermometers, barometers, etc.
In 1799 he proved that aqueous vapour exists in the atmosphere. In 1800 he published a paper on the con-
