We have leads in the lecture room which supply an arc-lamp for purposes of demonstration. Have you the necessary apparatus for conveying and connecting the current? If not, please communicate with Messrs Drake & Gorham, 2 Prince's Mansions, Victoria Street, and tell them what will be required. If you could spare time to come and see the place before-hand it would be an advantage.
Asst. Sec. R.S. [Assistant Secretary, Royal Society]'.