Coloured sky, evening twilight

Study of a multi-coloured sunset twilight, observed at the end of the rainy season in Loango, at the mouth of the Congo, Africa, 13 April 1876. Plate 6 from the book Untersuchungen uber Dämmerungserscheinungen zur Erklarung der nach dem Krakatau-ausbruch beobachteten atmospharisch-optischen Storung, by J. Kiessling (Hamburg, Leopold Voss, 1888). The plate is inscribed above: ‘Kiessling, Dämmerung-Untersuchungen. Taf. VI.’ Inscribed below: ‘MEHRFARBIGER DAMMERUNGSSCHEIN AM SCHLUSS DER REGENZEIT (ABEND). [Multicoloured twilight glow at the end of the rainy season, evening]. Pechuel-Loesche. Loangokuste, Loangobai, April 13. 1876. Chromolithographie von Leo Kempner & Co. in Hamburg. Verlag von Leopold Voss in Hamburg (und Leipzig).’ Karl Johann Kiessling (1839-1905) German physicist, replicated twilight glow phenomena in the laboratory. Eduard Moritz Pechuël-Loesche (1840-1913) German naturalist and watercolour painter who travelled widely, including on expeditions to the Congo, Africa.