The sun, photographed with a Dallmeyer heliograph, Vilnius, Lithuania, 1870

The sun, photographed with a Dallmeyer heliograph, Vilnius, Lithuania, 1870. Series of six photographic prints of the Sun dated September 1870 from the Wilna Observatory, Vilnius then part of the Russian Empire and now in Lithuania. These photographs were taken using a photoheliograph by Dallmayer, a photographic telescope based on an original instrument (Inv. No 1927-124) designed by Warren de la Rue (1815-1889). This series of images show the Sun at it most active, with the number of sunspots at its maximum. Samuel Heinrich Schwabe (1789-1875), a German astronomer, discovered this sunspot cycle in 1843. These solar photographs were displayed at the 1876 Loan exhibition, which was held on the site of today's Science Museum at South Kensington, London in England. ©SSPL/Science Museum