Records the measurements of sunspots taken at the Kew Observatory between the 24 January 1864 to 9 April 1872. The photographs were taken using the Kew photoheliograph designed by De La Rue in 1854. The break-though discoveries made at the Observatory on the influence of magnetism on sunspots, warranted an instrument that permitted the capture of daily photographs of sunspots. Funded by Benjamin Oliveira and commissioned by the Royal Society, Warren De La Rue designed the photoheliograph as the first purposely built apparatus to photograph astronomical bodies and phenomena. The original instrument is now kept at the Science Museum, London.