Unifying Prospects: Tinting Geological Maps in Nineteenth-Century Britain

Abstract

Geologically interested savants of the late eighteenth and early nineteenth centuries described three-dimensional spatial relationships through the visual language of maps and sections of the Earth. At this time, there was a debate whether colour or line should feature in mapping our strata. Colour was an identifying characteristic of Wernerian mineralogy, but the exact manner in which colour should be employed in representing a mineralogical landscape remained controversial. According to the engineer and geologist William Smith (1769–1839), words or symbols, engraved on a map, marred a visual simplicity that accommodated an immediate understanding of the area represented. Colour enabled a quick and rational study of the countryside so that the savant instantly visualized the logic of the landscape. André-Jean-Marie Brochant de Villiers (1792–1857), professor of geology and mineralogy at École des Mines, argued differently. In a letter to Thomas Webster (1773–1844), he remarked on the difficulty of correlating colours in the key with those of strata when studying Greenough's Map of England and Wales (1819). By examining techniques of representation and the use of colour, this paper discusses the importance of aesthetics in the depiction of geological landscape.