Published online by Cambridge University Press: 05 January 2009
George Greenough (1778–1856) was one of the influential group of early nineteenth-century English geologists who rejected both Hutton's and Werner's attempts to propound all-embracing geological theories, and followed a deliberately empirical approach. He travelled through Scotland in 1805, studying geological phenomena in the light of both the Plutonist and the Neptunist theories, and generally concluded that neither was entirely satisfactory as an explanation of the observable facts. He was also the first to suggest that the ‘Parallel Roads’ of Glen Roy were the successive beach-levels of a former lake: this theory was later attacked by Darwin but ultimately vindicated by Agassiz's glacial theory. The more important geological passages from Greenough's MS. journal of the tour are reproduced and discussed in this paper. They illustrate some of the scientific problems that were involved in accepting either Hutton's or Werner's theory entire.
1 I am greatly indebted to the present owner of the Greenough Papers for giving me the opportunity to study them.
2 He never studied under Werner or even visited Freiburg, contrary to the statement in the Geological Society's obituary of him (Proc. Geol. Soc., 1856, xii, p. xxvii).Google Scholar
3 Trans. Geol. Soc., 1817, 1st series, iv, 314–392.Google Scholar
4 Many years later, Charles Lyell wrote to Greenough, (28 11 1834)Google Scholar: ‘I know by experience that you only allow your original observations to steal into the world some 10 or 20 years after they are made thro' other authors' works.’ On another occasion, Lyell noted MacCulloch's ‘disposition to neglect or speak slightingly of the labours of others’ (Proc. Geol. Soc., 1836, ii, 359).Google Scholar
5 ‘Observations on the Parallel Roads of Glen Roy’, Phil. Trans. Roy. Soc., 1839, 39–81.Google Scholar
6 ‘The Glacial Theory and its Recent Progress’, Edin. New. Philos. J., 1842, xxxiii, 217–282.Google Scholar
7 Cf. John, Playfair, Illustrations of the Hultonian Theory, Edinburgh, 1802Google Scholar, §293.
8 Cf. John, Whitehurst, An Inquiry into the Original State and Formation of the Earth …, 2nd ed., London, 1786Google Scholar: chapter XVI, ‘Of the Strata in Derbyshire and other Parts of England’.
9 Sills and lava-flows of olivine dolerite.
10 Werner's claim to have found such a transition was a cornerstone of Neptunist theory. His interpretation of the Schiebenberg was reprinted by Jameson, in A mineralogical Description of the County of Dumfries, Edinburgh, 1805, pp. 180–185.Google Scholar
11 Cf. Playfair, op. cit., §190. Horizontal Upper Old Red Sandstone rests on vertical Silurian slates and greywackes.
12 Probably a slip of the pen: Hall's views are, of course, Plutonist.
13 His ‘Account of a Series of Experiments, shewing the Effects of Compression in modifying the Action of Heat’ had been read a month previously (3 June 1805), but was not published in full until 1812 (Trans. Roy. Soc. Edin., vi, 71–185).Google Scholar
14 Cf. Playfair, op. cit., §63.
15 Cf. Playfair, op. cit., §§67, 243, 255, 259, 262.Google Scholar
16 Hope, Thomas (1766–1844), Professor of Chemistry at Edinburgh, 1795–1843.Google Scholar
17 Cf. Playfair, op. cit., §§184–185.
18 Cf. Playfair, op. cit., §65.
19 Part of the Tertiary Ardnamurchan igneous complex.
20 Part of the Tertiary Hebridean dyke-swarm.
21 Lower Liassic Pabba Shales.
22 Cf. Playfair, op. cit., §69.
23 Cf. Jameson, R., 1800, Scottish Isles, ii, 52–53.Google Scholar
24 Hailstone, John (1759–1847), Woodwardian Professor of Geology at Cambridge, 1788–1818.Google Scholar
25 Cf. Jameson, , op. cit., ii, 44–6.Google Scholar
26 Cf. Jameson, , op. cit., i, 213–220.Google Scholar
27 A small appended sketch shows one dyke tapering out as another expands en echelon.
28 Playfair, op. cit., §20.
29 Middle Old Red Sandstone.
30 Cf. Playfair, op. cit., §§82, 277Google Scholar; Jameson, , op. cit., ii, 164–169.Google Scholar
31 Cf. Playfair, op. cit., §§68, 266Google Scholar; Jameson, op. cit., i, 75.Google Scholar