D ALTON 115 



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 Dal ton 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 stock- 

 ings 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 be- 

 tween 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- 



