James Timmins Chance to Faraday   22 November 1860

Hamstead | Birmingham | 22 Nov: 1860

My dear Sir,

Our respective notes of yesterday¹ have crossed each other on the road.

I shall not have the two complete panels - new arrangement, & old one - ready by Monday: but everything shall be quite ready for Thursday next.

I have all requisite plans for shewing each zone by itself, by means of wooden screens, which can be moved vertically.

The height of the lamp wh: best suits each Zone is obtained by a screw motion, by wh: the plate carrying the lamp is raised or lowered.

I obtain the best position of the burner for each Zone, and then observe the direction of the focal line of that Zone in relation to the burner.

It was by this means that I arrived at the positions of foci, wh: I sent to you yesterday.

If I had chosen 21mm, my original height, for the middle belt focus, the figures wd have been more symmetrical.

I am most anxious to have your own assistance in determining the brightest positions, in relation to the burner, of the focal line of the belt & each Zone.

Above & below the middle belt, as I said before, it is a question of the brightest tint, those being in each case the red, yellow, & blue images of the flames superimposed at different inclinations[.]

Most truly yours | J.T. Chance