Copy letter from [William] Spottiswoode, President of the Royal Society; to Sir Julian Pauncefote, Assistant UnderSecretary for Foreign Affairs. Replies in reference to a pamphlet sent in on the request of Earl Granville [Granville Leveson-Gower] regarding a water filteration process by Prof. Almen of Upsala University [Sweden]. In regards to using the process in Egypt, forwards the explanation of the President [William Spottiswoode], that the process is well known, and although clarifies the water, does not make bad water good, and does not suggest its use for the Egyptian campaign. States the best method would be distillation, which will remove the germs as well. 12 September 1882