The Athenaeum Club - JDF has read an account of the BAAS Dublin meeting and Professor Powell's [Baden Powell] account of Melloni's [Macedonio Melloni] and JDF's experiments: 'His chief object seems to have been to make out the accuracy of his own papers, and he certainly mistakes Melloni's results as completely as it is possible to do when he makes him say that there are two distinct kinds of heat. On the contrary there are an infinite variety which pass into one another insensibly. He equally mistakes my results when he makes them to depend upon Mr Murphy's [Robert Murphy, Elementary Principles of the Theories of Electricity, Heat, and Molecular Actions, 1833] Integration. This is precisely Biot's [Jean Baptiste Biot] objection, viz that the two positions of the plates are not symmetrical as regards the effect of conduction [JDF gives a diagram showing the angles of the plates]. Granted at once. But will the mathematical gentlemen only have the goodness to see the experiment tried and they will see that the effect is of an order quite superior to any effect of conduction whatever - that it is independent of the distances of the plates from one another, which requires, no nicety of adjustment, so that the integration (if practicable) will go for nothing. I have really a right to insist that my experiments shall be seen before they are judged. I admit all the mathematical perturbations, but the chief cause is as clearly developed as the influence of the moon on the tides'. The tables have turned in Paris in favour of JDF's theory: 'Arago [Dominique F J Arago], Libri [Guglielmo Libri] and Dulong [P. L. Dulong] have taken up my cause, Biot is at last silenced'. Could WW point out to Mr Murphy [Robert Murphy] 'that in the case of Depolarization by the mica plate there is the most perfect symmetry (mathematically) which he can desire'.
Includes an incomplete letter from [Luke Howard?] dated 18 June 1835 (item 1), "Representation of a Committee appointed by the British Association assembled at Dublin, August 1835" (item 4), "Temperature observed at Woodbine Hall, in the County of Norfolk, at different periods of a Solar Eclipse, on May 15, 1836" (item 5); draft report on Mr Herapath's experiment (item 7); a fair copy[?] of "Sequel of the Researches upon the Measure of Temperatures & upon the Laws of the commication of heat by M. M. Dulong and Petit, Second Part" (item 9); instructions for taking readings [in the Dolcoath mine?] (item 10); notes "On the change of action in an Iron-ship's compasses from a stroke of lightning" (item 13); a notebook entitled "Experiments on Elastic Balls" (item 14); three mechanical copies of a sheet headed "Atomic Symbols" (items 17-19); and printed "Notice of a species of Seal apparently new to the British Shores" by W. B. Clarke, 14 Aug. 1847 (item 22).