Letter from Mr Roberts, 54 Upper Tollington Park, London, to [George James] Symons, [Chair of the Royal Society Krakatoa Committee] Forwarding a copy of the notes of Captain A. Sampson, who was in the Sunda Straits, during the eruption of Krakatoa, and his brother, who crossed the line at the same time, as well as a sample bottle of pumice dust collected on deck, and pumice found 80 miles off the shore. 18 February 1884