TALBOT1677

Park Square
Monday

My dear Sir

I can only repeat my suspicion that some of our organs must be differently constituted from those of some others ¹ – Herschel ² agrees with me in the effect of snapdragon: but in this there may be some falacy, from the want of actual red to show the cheeks and the lips: but when I look at the spectrum as I have coloured it, and compare the figure with Fraunhofer’s ³ I cannot persuade myself that we have been painting from the same original – I have not examined the flame of cyanogen: I conclude you are well acquainted with that of the bottom of a candle which is very striking – I suppose the theatrical light is from tin. Is the pale light of cyanogen beyond the common spectrum?

I shall be truly glad to see your investigations in print – and as Fresnel’s ⁴ outlines are now nearly finished in Brande ⁵ this would form a very good continuation of the subject.

Your words were “Just so will any number [destroy each other] if equidistant, except in one case – when they all strengthen each other” and you now say, that the sum of the sines is finite only when x = 0, 360º, &c” –

My observation was that when the number is finite the sum is not = 0 in cases like that which I mentioned –

I am still at a loss to conceive how you get an infinite number, or even a very large number of centres of divergence in perfect accordance But I must wait for your paper.

I have nothing to do with force, inversely as the distance – we have problems enough, in all conscience, that are natural without adding artificial ones –

Believe me Dear Sir very truly yours
Thomas Young

H. Fox Talbot Esq
31 Sackville Street