[2808] Norman Conquest, i, xv.
[2809] Longius delatus aestu (B. G., v, 8, § 2). According to Long (Decline of the Roman Republic, iv, 1872, p. 204), ‘the expression “too far” (longius) means that he was carried too far north and past the place where he had landed the year before.’ But as the direction of the current was ENE. (magnetic), the smallest drift would have been too far.
[2810] B. G., v, 8, § 2.
[2811] See pp. 728-30, infra.
[2812] Zeitschrift für allgemeine Erdkunde, xviii, 1865, pp. 122-3. There is an obvious objection to this argument, to which Heller replies by anticipation. One of the three sides of Britain, says Caesar, looks southward towards Gaul; and one of the ‘angles’ (alter angulus) of this side is by Kent (B. G., v, 13, § 1). If Caesar landed, as Heller believes, between the South Foreland and the North Foreland, he had himself seen this angle, which is formed by the South Foreland; and if he believed that the coast, at the North Foreland, turned sharply towards the west, and had no knowledge of that part of the coast which trends northward beyond the mouth of the Thames, it is clear that he must have regarded the North Foreland and not the South Foreland, as marking the commencement of the northern side, in which case one might think that he would have described the coast between the South Foreland and the North Foreland as a separate side, and would have represented Britain not as triangular but as irregularly quadrilateral. But Heller argues that the word angulus, as used by Caesar, does not mean an ‘angle’ in the geometrical sense of the word, but only a strip of coast between two angles; and he compares a passage in Livy’s description of the siege of Saguntum (xxi, 7, § 5),—Angulus muri erat in planiorem patentioremque quam cetera circa vallem vergens.
[2813] Caesar started ‘about sunset’ (ad solis occasum): the wind dropped ‘about midnight’ (media circiter nocte); and the drift ceased at daybreak (orta luce). The sun set at 8.16 p.m.; and day broke about 3.20 a.m. It would be absurd to suppose that the voyage must have begun at the moment when the sun dipped under the horizon: we may fairly assume that it began at any time between 7 and 8. Similarly the drift may be assumed to have begun at any time between 11 p.m. and 1 a.m. Let us suppose that the wind lasted 5 hours, and the drift 3 hours. For some time before the wind dropped it must have been gradually dying down; but, as the vessels kept steerage way, it may be assumed, so Captain Iron, the harbour-master at Dover assures me, that, even during the drift, there was not a dead calm. Major Rennell, indeed, affirms (Archaeologia, xxi, 1827, p. 503) that when the wind dropped the ships were ‘left to the resources of their oars’: but Caesar does not confirm this; and if the oars had been used, why should the ships have drifted out of their course? Captain Iron says that with a light south-westerly wind the ships could easily have sailed 6 knots an hour. The voyage took place about the time of new moon (see pp. 728-30, infra), that is to say, a day or two before spring tide. For the first two hours the ships had to encounter the ebb tide, the rate of which, however, was not more than one knot an hour; and the flood, the rate of which increased from about three-quarters of a knot to nearly 3 knots, helped them from about 9 or 9.30 p.m. We may estimate, then, that in the 5 hours they sailed not less than 25 knots; while in 3 hours, aided by a faint breeze, they would have drifted about 6 knots (see p. 656, infra). I think, then, that the entire distance which Caesar sailed up to the moment when he ‘saw Britain lying behind on the port quarter’, may be estimated at not less than 31 knots, or about 57½ kilometres. After making this calculation, which must be taken for what it is worth, I find that, according to Napoleon’s map (Hist. de Jules César, Atlas, pl. 16), the distance was 57 kilometres. The reader may check my estimate by referring to the Admiralty Tide Tables, pp. 112-9, and Tidal Streams, English and Irish Channels.
[2814] See Tide Tables for the British and Irish Ports, p. 119.
[2815] For this reason I attach no importance to Heller’s remark (Philologus, xlix, 1890, p. 692), that, if Caesar had only drifted as far northward as the latitude of Deal, he would have written, not sub sinistra Britanniam relictam conspexit, but longius se a Britannia recessisse animum advertit.
[2816] Zeitschrift für allgemeine Erdkunde, xviii, 1865, p. 176; Philologus, xlix, 1890, pp. 691-2.
[2817] Origines Celticae, ii, 362.