Faraday to James Booth¹   1 November 1860

Royal Institution | 1st November 1860.

Sir

Having received intimation of the intention of My Lords, I had already proceeded to Birmingham before I received your letter of the 30th², and was there on the 29th and 30th of October last, examining the Optical apparatus referred to, both by day & night. I found it quite satisfactory. Very refined methods of adjusting the various pieces of glass constituting the apparatus have been devised recently, and have been applied in the present instances. I have verified the work by equally exact processes; and the results when the lamps were lighted, and the course of the rays traced out to a distance, were such as to give one full satisfaction[.] The general character of the glass in colour, and other points of quality, was good.

It is essential that the lamps in a lighthouse should burn well and be easily preserved in order. Those at Birmingham were new, and the pressure and overflow of oil did not seem sufficient:- perhaps some accidental obstruction occurred in some of the oil passages. It is scarcely in my department; nevertheless I take the liberty of calling the attention of Mr. Parkes³, the Engineer, to the circumstance; the more especially as the apparatus, being destined for service in the Red Sea, cannot easily be examined and rectified after it is once left. The oil which overflows and passes round unburnt, should be three times as much as that which is consumed: Of course it is returned to the cistern.

I have the honor to be | Sir | Your Very Obedient humble Servant | M Faraday

James Booth Esqr | &c &c &c &c | Privy Council for Trade | Whitehall