Intelligence and Miscellaneous Articles. 323 



ened in English, in return another is softened. But, then, does Sir 

 William think that the proper tone is hit in his memoir, in which 

 such expressions as " clumsy way," " commonplace and unsound 

 objection," and "somewhat learned endeavour," are made use of 

 against me? If so, I need no excuse for having adopted a tone 

 which he thinks improper. 



In reference to his memoir in the Philosophical Transactions for 

 1 834, I have charged Sir W. Harris with want of the necessary 

 knowledge. Such a charge must be put up with by every one who 

 draws from experiments untenable results, which it would have been 

 impossible for him to have done had he been acquainted with the 

 works of Franklin, ^pinus. Coulomb, and Poisson. 



I am compelled to assume, that, nineteen years ago, I demonstrated 

 that law of electrical heat which is attacked by Sir William, and 

 that it has not yet been refuted. This law is not one of the points 

 of my electrical labours regarding which doubts have been raised ; 

 on the contrary, it has been accepted by all physicists who treat of 

 electricity in detail, and has proved to be in complete agreement 

 with all the experimental and theoretical investigations which have 

 since been made. If Sir W. Snow Harris be in a position to show 

 the untenability of this law, he will do good service to science. 



I am not quite clear as to what the author aims at with the resist- 

 ance in the battery. If Sir William supposes the resistance between 

 glass and coating to be constant when the battery is enlarged, 

 he produces no change in my formulae, in which the sum of all con- 

 stant resistances is indicated ; if he regards this resistance as variable, 

 he throws over his own law of electrical heat. 



In the following remark. Sir William is partly right. In my letter 

 it runs, it is " nicht richtig " (which corresponds with the English 

 " not correct") that I ascribed the unsatisfactory experiments of Sir 

 W. Harris to the " faulty arrangement " of his thermometer. I 

 had before me my original German memoir of 1837 (which I also 

 referred to), in which the censure pronounced cannot be applied to 

 the thermometer, but it had entirely escaped me that in 1838, I had 

 worked up this memoir in French, when I ascribed those experiments 

 to the imperfect (imparfaite) construction of the thermometer. It is 

 therefore clear that I attempted to account to myself for the failure 

 of Harris' experiments in different ways at different times, — by the 

 inexact mode of measuring the electricity, the faulty mode of dis- 

 charging the battery, and the want of sensibility in the thermometer. 

 Latterly the first two causes appeared so sufficient to me, that I forgot 

 the third. 



' Sir William characterizes the heat- experiments of Kinnersley with 

 the thermometer as " casual," " a mere coincidence," " quite a se- 

 condary affair," and asserts that the experiments came to no result, 

 which must raise the astonishment of any one who has ever even 

 glanced at Kinnersley's letter. Kinnersley invented his thermometer 

 solely with the view of refuting an opinion of Franklin's regarding the 

 electrical heat, and introduces it with the words, " it fully determines 

 that controverted point, whether there be heat in the electric fire." 

 He deduces from his experiments the important point, " Hence it ap- 



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