[3003] See the note at the end of Airy’s article in Archaeologia, xxxiv, 1852; Sir C. Lyell, Principles of Geology, 1875, p. 534; and Proc. Inst. Civil Engineers, clix, 1905, p. 129.
[3004] Archaeologia, xxxiv, 1852, pp. 239, 242.
[3005] B. G., iv, 23, § 2.
[3006] Viscount Wolseley, The Soldier’s Pocket-Book, 1886, p. 491.—‘Good eye-sight can distinguish bodies of troops at 2,000 yards; at that distance a man or horse appears like a dot; at 1,200 yards cavalry is distinguished from infantry,’ &c. I am aware that in certain primitive districts, for instance the islands of Inishbofin and Inishshank off the coast of Galway, the average range of vision is abnormally great (Proc. Roy. Irish Acad., 3rd ser., iii, 1893-5, p. 324); but we may reasonably assume that Caesar could not see eight or nine times as far as a modern Englishman.
[3007] The Invasion of Britain, &c., 1862, p. xxxiv.
[3008] See p. 610, supra, and Tide Tables for the British and Irish Ports, p. 225.
[3009] Archaeologia, xxxiv, 1852, p. 239.—‘At full and change of the moon,’ says Admiral Beechey, ‘close in shore off Hastings the stream turns to the west at 11h; but the turn becomes later as the distance off shore increases, and at 5 miles distance the stream turns to the west at 1h.... The stream runs to the west about 6½ hours,’ &c.
[3010] Airy himself, as we have seen, makes no allowance for any variation which may have been produced by wind or other causes from the normal hour of the turn of the stream. I am willing to make any reasonable allowance; but the intelligent reader will have seen that no such allowance would disturb the conclusion which I have reached in the text.
[3011] See pp. 648-9, infra.
[3012] B. G., iv, 28, § 2.