The development of the atomic theory.

  • Andrew Norman Meldrum
Date:
[1910-1911]
Catalogue details

Licence: In copyright

Credit: The development of the atomic theory. Source: Wellcome Collection.

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    with the appearance of a deliberate, strategical, irresistible advance. On examination his narrative, in spite of its grand air, is found to throw much less light than it pro- mises on the line of thought and train of investigation which he pursued. It is excessively abstract in tone, and avoids going into details and particulars and instances. It does not tell us what we want to know most, how and when Dalton arrived at the law of multiple proportions, and the part played by the law in the construction of the theory. Information on these matters is what is wanted, and anything else is beside the point. Yet there is one novel element in Dalton’s account. This is the suggestion that the formation of the chemical atomic theory took place subsequently to the amendment of the diffusion theory. But, as the notebooks show, the chemical theory was formed in 1803. Hence, Roscoe and Harden conclude that 1805, the date which Dalton assigns to his amended diffusion theory, should be 1803.23 Reasons will be given later, in a paper on Dalton’s physical atomic theory, for thinking that the narrative is doubtful on the only point on which it presents any novelty. Conclusion. There are in existence yet other accounts of this matter. One is given by Dalton’s pupil, Joseph A. Ran- some,24 and another by Dalton himself. This was in the lecture which he delivered to the members of the Mechanics’ Institute in Manchester on October 19th, i835.S5 The main feature, which all the accounts have in 23 Op. cit., p. 25. 24 W. C. Henry, Op. cit., pp. 220-222. 26 Manchester Times, October 25, 1835.
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