JOHN D ALT ON 5°5 



circumstances is notorious. Others, like George Green, received no 

 recognition whatsoever. In addition, the English passion for inde- 

 pendence played its part. The demand for complete freedom, if it 

 fostered the eccentricity of which the docile, drilled Germans com- 

 plained, although it led to pig-headedness, as in Dalton's case, also 

 proved greatly favorable to original genius. For, it is well to recall 

 that more original notions, basal to modern science, have come from 

 England than from any other land, even if, as with Newton and Dar- 

 win, France was to systematize Newtonianisme, Germany Darwinismus. 

 England possessed no trained regiments to accomplish these things. 

 Accordingly, if we remember all this, some apparent mysteries that 

 cloak Dalton's career and mental characteristics begin to dissipate. In 

 short, the Dalton we commemorate would have been nigh inconceivable 

 had he been " born to the intellectual purple of the ancient universi- 

 ties " ; but the Dalton we regret, who remained obdurate to Gay-Lussac 

 despite Berzelius's intercession, might never have been. The qualities 

 of the man, like his defects, pertained to his strong, wayward and un- 

 disciplined, if narrow and often uncouth, provincialism. Qui a nuce 

 nucleum esse vult, frangat nucem. 



II 



Dalton maintained silence from 1793 till 1799, hindered, perhaps, 

 by college duties. On reappearance, he soon dropped the role of meteor- 

 ologist for that of chemist and physicist. The new line was taken in 

 the paper entitled " Experiments and Observations on the Power of 

 Fluids to Conduct Heat, with Reference to Count Eumford's Seventh 

 Essay on the same Subject," read before the Manchester Society on 

 April 12, 1799. The simple nature of his apparatus may be illustrated 

 aptly from this communication. 



Took an ale glass of a conical figure, 2i inches in diameter, and 3 inches 

 deep; filled it with water that had been standing in the room, and consequently 

 of the temperature of the air nearly. Put the bulb of a thermometer in the 

 bottom of the glass, the scale being out of the water; then having marked the 

 temperature, I put the red-hot tip of a poker half an inch deep in the water, 

 holding it there steadily for half a minute; and as soon as it was withdrawn, 

 I dipped the bulb of a sensitive thermometer about J inch, when it rose in a 

 few seconds to 180°. u 



Then follow the tabulated temperature results. Another experi- 

 ment, described in the same paper, suffices to show that Dalton had 

 pondered the discontinuity of matter thus early. Having mixed hot 

 and cold water for half a minute, he proceeded to determine whether the 

 upper layer became warmer than the lower. Observing that it did not, 

 he remarked : " If the particles of water during the agitation had not 



14 Memoirs of the Literary and Philosophical Society of Manchester, Vol. 

 V., p. 381. 



