Faraday to James Timmins Chance   21 September 1860

Hampton Court Green¹ | 21, Septr. 1860

My dear Sir

I have only just had your letter here². So write to the Royal Hotel, Whitby.

You just touch the thing that completely puzzles me namely the French arrangement[.] I am most anxious not to meddle with the North light at all but keep that as a record of the past state. Then I think we cannot spare two octants for the French adjustments. Yet as M. Sautre [sic] & the French authorities say that such a dip as the North Foreland - which is near 200 feet is unimportant, I should be sorry not to include proof of the effect:- though having that as the French have it we do not correctly compare the pure effect of different foci.

I cannot but think that the Trinity house will expect to see one of the octants as M. Sautre would have it and have the power of comparing it with an octant as we should have it - the lamp being the same & to this purpose I had directed Octants 2 & 3. Of the other two octants 1 & 4 I should be sorry to lose the instruction we hope to derive from them. No. 1. I expect will throw the light more to the horizon. No. 4 more below it - and even more below it than No. 2. Yet you speak well of it as if you wished for it. If we throw either out in order to introduce the French foci subordinate to the Sea horizon, I should wish it to be Octant 4. (focus 28 above & 40 aside). What do you think of that.

I asked you for a round sum as estimate of expences³[.] Has it escaped your memory or have you sent it in to the Trinity House? I have to add a few pounds to it before it goes in[.]

Ever Your | M. Faraday

J.T. Chance Esq | &c &c &c

Could you get the correct bearings by the Compass of the division lines between the Octants. I suppose the agent will be kind enough to give them to you?

Yours | MF