Prout’s law

Soc., 31, 337,1881) has tried to answer the question, Is the number of harmonic relations in the spectral lines of iron greater than what a chance distribution would give Mallet (Phil. Trans., 171,1003, 1880) and R. J. Strutt (Phil. Mag., [6], 1,311,1901) have asked, Do the atomic weights of the elements approximate as closely to whole numbers as can reasonably be accounted for by an accidental coincidence In other words Are there common-sense grounds for believing the truth of Prout s law, that the atomic weights of the other elements are exact multiples of that of hydrogen ... 

William Prout s composite atoms hypothesis. G. Kirchhoff and R. Bunsen discover spectral analysis and significance of Fraunhofer lines Kirchhoff s law. 

Modern writers on the periodic system have tended to downplay Prout s hypothesis, perhaps due to Whiggish tendencies and the fact that it has turned out to be incorrect. One exception is F.P. Venable s classic history of the early stages of the periodic system, in which he makes the following highly laudatory remark about Proufs idea Probably no hypothesis in chemistry has been so fruitful of excellent research as this much discussed hypothesis of Prout The Development of the Periodic Law, Chemical Publishing Co., Easton, PA,1896,p. 3). 

N = number of textbooks (including new editions and translations). 0 = textbooks without any reference to periodic law M = textbooks mentioning periodic law T= textbooks with tables representing the periodic law Classifications = Classifications used as organizing principles of the textbook P = textbooks including a reference to the prediction of new elements Prout = textbooks relating the periodic law to Prout s hypothesis in... 

Up to this point, Bertholet s critique seemed to have been very reasonable, but in this final remark he gave Mendeleev an easy way of responding.Mendeleev took issue in particular with Bertholet s reference to a mystic enthusiasm and responded by accusing Bertholet of confusing the idea of the law of periodicity with the ideas of William Prout, as well as with those of the alchemists and of Democritus on primary matter. It was in response to these criticisms by Bertholet that Mendeleev also made a much quoted remark, already cited in chapter 4, in which he emphasized that the periodic system owed nothing to the idea of a unique matter and had no connection with the relic of the torments of classical thought. ... 

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