[722] Sul Tempio di Serap. ch. viii.

[723] Tavola Metrica Chronologica, &c. Napoli, 1838. Mr.

Smith, of Jordan Hill, writing in 1847, estimated the rate of subsidence, at that period, at _one inch_ annually. Quart.

Journ. Geol. Soc. vol. iii. p. 237.

[724] Voy. dans la Campanie, tome ii. p. 162.

[725] Mr. Forbes, Physical Notices of the Bay of Naples. Ed.

Journ. of Sci., No. II., new series, p. 280. October, 1829.

When I visited Puzzuoli, and arrived at the above conclusions, I knew nothing of Mr. Forbes's observations, which I first saw on my return to England the year following.

[726] Quart. Journ. Geol. Soc. 1847, vol. iii. p. 203.

[727] Nuove Ricerche sul Temp. di Serap.

[728] The Swedish measure scarcely differs from ours; the foot being divided into twelve inches, and being less than ours by three-eighths of an inch only.

[729] For a full account of the Celsian controversy, we may refer our readers to Von Hoff, Geschichte, &c. vol. i. p. 439.

[730] Piteo, Luleo, and Obo are spelt, in many English maps, Pitea, Lulea, bo; the _a_ is not sounded in the Swedish diphthong _ao_ or __.

[731] Sect. 393.

[732] Sect. 398.

[733] Transl. of his Travels, p. 387.

[734] In the earlier editions I expressed many doubts as to the validity of the proofs of a gradual rise of land in Sweden. A detailed statement of the observations which I made in 1834, and which led me to change my opinion, will be found in the Philosophical Transactions for 1835, part i.

[735] See Professor Johnston's Paper, Ed. New Phil. Journ. No.

29, July 1833; and my remarks, Phil. Trans. 1835, p. 12.

[736] See p. 522; also chap. 15, _supra_.

[737] See a paper by the Author, Phil. Trans. 1835, part i.

[738] See my paper before referred to, Phil. Trans. 1885, part i. p. 8, 9. Attempts have been since made to explain away the position of this hut, by conjecturing that a more recent trench had been previously dug here, which had become filled up in time by sand drifted by the wind. The engineers who superintended the works in 1819, and with whom I conversed, had considered every hypothesis of the kind, but could not so explain the facts.

[739] Quart. Journ. of Geol. Soc. No. 4, p. 534. M. Bravais'

observations were verified in 1849 by Mr. R. Chambers in his "Tracings of N. of Europe," p. 208.

[740] See Proceedings of Geol. Soc. No. 42, p. 208. I also conversed with Dr. Pingel on the subject at Copenhagen in 1834.

[741] Keilhau, Bulletin de la Soc. Geol de France, tom. vii.

p. 18.

[742] Ill.u.s.t. of Hutt. Theory, -- 435-443.

[743] Herschel's Astronomy, chap. iii.

[744] See Hennessy, On Changes in Earth's Figure, &c. Journ.

Geol. Soc. Dublin, 1849; and Proc. Roy. Irish Acad. vol. iv.

p. 337.

[745] Young's Lectures, and Mrs. Somerville's Connection of the Physical Sciences, p. 90.

[746] Phil. Trans. 1839, and Researches in Physical Geology, 1st, 2d, and 3d series, London, 1839-1842; also on Phenomena and Theory of Volcanoes, Report Brit. a.s.soc. 1847.

[747] Ed. Journ. of Sci. April, 1832.

[748] Cordier, Mem. de l'Inst.i.t. tom. vii.

[749] Pog. Ann. tom. xv. p. 159.

[750] See M. Cordier's Memoir on the Temperature of the Interior of the Earth, read to the Academy of Sciences, 4th June, 1827.--Edin. New Phil. Journal, No. viii. p. 273.

[751] Cordier, Mem. de l'Inst.i.t. tom. vii.

[752] Phil. Mag. and Ann. Feb. 1830.

[753] The heat was measured in Wedgwood's pyrometer by the contraction of pure clay, which is reduced in volume when heated, first by the loss of its water of combination, and afterwards, on the application of more intense heat, by incipient vitrification. The expansion of platina is the test employed by Mr. Daniell in his pyrometer, and this has been found to yield uniform and constant results, such as are in perfect harmony with conclusions drawn from various other independent sources. The instrument for which the author received the Rumford Medal from the Royal Society, in 1833, is described in the Phil. Trans. 1830, part ii., and 1831, part ii.

[754] The above remarks are reprinted verbatim from my third edition, May, 1834. A memoir was afterwards communicated by M.

Poisson to the Academy of Sciences, January, 1837, on the solid parts of the globe, containing an epitome of a work ent.i.tled "Theorie Mathematique de la Chaleur," published in 1835. In this memoir he controverts the doctrine of the high temperature of a central fluid on similar grounds to those above stated. He imagines, that if the globe ever pa.s.sed from a liquid to a solid state by radiation of heat, the central nucleus must have begun to cool and consolidate first.

[755] Consolations in Travel, p. 271.

[756] Phil. Trans. 1830, p. 399.

[757] Biblioth. Univers. 1833, Electricite.

[758] Phil. Trans. 1832, p. 176; also pp. 172, 173, &c.

[759] Hist. Mundi, lib. ii. c. 107.

[760] Reduced, by permission, from a figure in plate 40 of Sir H. De la Beche's Geological Sections and Views.

[761] Phil. Trans. 1828, p. 250.

[762] Geology of American Exploring Expedition, p. 369.

[763] Davy, Phil. Trans. 1828, p. 244.

[764] Ann. de Chim. et de Phys. tom. iii. p. 181.

[765] Phil. Trans. 1832, p. 240.

[766] Ann. de Chim. et de Phys. tom. xxii.