[23] “Cosmos,” vol. i., p. 25. Bohn.
[24] “Cosmos,” vol. i., p. 237.
[25] Darwin’s “Journal,” p. 291, 2nd edition.
[26] “Elements of Geology,” p. 732.
[27] Ibid, p. 733.
[28] Lyell’s “Elements of Geology,” p. 617.
[29] Lyell’s “Elements of Geology,” p. 620.
[30] Ibid, p. 620.
[31] Report of the Royal Cornwall Polytechnic Society for 1837. Robert Hunt, in “Memoirs of the Geological Survey of Great Britain,” vol. i., p. 433.