Letter from William Huggins, 90 Upper Tulse Hill, S W [South West] London, to the Secretary [Joseph Larmor] Huggins has developed the photograph and was shocked to find the N spectrum now reappeared and that there seems to be no continuous spectrum from the results. The Ra has turned brown and is less luminous. The H probably affects the rate of production of emanations in Ra, and it would seem that N is slowly produced. There was no trace of N in the former photos. Huggins notes he must not say anything to Cambridge. c December 1908