Charles Robert Leslie to Faraday   22 May 1854¹

2 Abercorn Place | St John’s Wood | May 22nd 1854

Dear Sir,

Availing myself of the enclosed introduction from Sir Benjn Brodie, I beg you will allow me to ask a question which I feel sure nobody can answer so well as yourself; otherwise I should not think it right to intrude, for a moment, on time so valuable as yours.

I have thoughts of publishing some essays on painting², and I should be glad to know whether or not I am right in supposing that the azure of the sky is occasioned by particles of water in a more complete state of solution than the vapour of which the clouds are composed, the local colour of water being, as Professor Wheatstone tells me, blue.

I have fancied also that air, unimpregnated with water, would be invisible; and that (supposing the absence of water from the atmosphere) the space in which we see the sun and the other heavenly bodies would appear utterly stark, while these luminaries would be much more intensely light than we see them, and without any appearance of halo or rays.-

These suppositions may betray, to you, great ignorance, - but I am sure you will know how to excuse it.- I have only to add that I am in no immediate want of a reply, but that I shall feel greatly obliged by one, when it may best suit your convenience so to favour me.

I am, | dear Sir, | yours obediently, | and with great respect | C.R. Leslie

Michael Faraday Esq | F.R.S. &c &c.