William Whewell to Faraday   22 November 1848

Trin. Lodge, Cambridge Nov. 22 | 1848

My dear Sir

I am encouraged by your approval¹ of my proposed subject to take courage to give you a lecture at the R.I.² I am not certain that the 19th of January will be so convenient to me as the 26th; but perhaps you will allow me to leave this point open a little longer. In your letter of the 7th³ you mention Plucker's papers in Poggendor[f]f⁴. Can you give me the n˚ of the volume, for I have not been able to find the papers which you refer to.

In the expts on crystals which you describe, you find the axis of maximum pointing force by making vertical the axis which was originally horizontal and equatorial. This I do not understand, because it appears to me that what axis is originally horizontal must depend on an arbitrary condition, the original point of suspension. But of course my difficulty arises from not understanding the thing.

I shall want much to see what you say about axiality. But we shall have to consider whether axiality does not apply to some cases which we have been accustomed to call polarization. For instance is not the polarization of light a sort of axiality? A vertical ray polarized in plane NS is not distinguishable from a vertical ray polarized in plane SN. But I see fully the importance of the distinction in electro-chemistry, and have no doubt that the true general distinction will disclose itself as you go on, if it have not done so already. I am quite impatient to see your new paper⁵.

I have been reading over your Researches. I have always had a difficulty about your Induction in curved lines as an original law. I have put down on another paper⁶ my difficulty stated as it occurs to me. I should be glad if when you have time you could tell me where I am wrong. I do not ask this in reference to anything I may have to say at the R.I. for I do not foresee daring to touch upon the subject; but I should like to possess your views clearly.

I am always |Very truly yours | W. Whewell

Dr Faraday