The plates were produced by a mixed process of photographic transposing on to a metal plate (heliograph) followed by handwork of various kinds soft-ground etching, mezzotint and aquatint, the background tint being achieved by lithography (D.H. Boalch, Prints and Paintings of British Farm Livestock, 1780-1910, 1958). Nadar (Gaspard Félix Tournachon, 1820-1910) was celebrated for his photographic portraits.
References: Nissen ZB1 257.
Baudement (Émile) Les races bovines au concours universel agricole de Paris en 1856. Études zootechniques, 87 fine heliographed plates by A. Riffaut and others after drawings by Emile Van Marke and others from photographs by Nadar, later hand-colouring throughout, 2 plates misbound (76 and 77), without the accompanying text or 5 coloured maps, contemporary green morocco-backed cloth, rubbed, one corner worn, oblong folio (352 by 475mm.), Paris, Imprimerie impériale, 1861[-1862]