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This webpage reproduces an article in the Classical Review Vol. 28 (1914), pp193‑196 The text is in the public domain: T. Rice Holmes died in 1933. This page has been carefully proofread and I believe it to be free of errors. If you find a mistake though, please let me know!

 p193  Portus Itius.​1

I have been abroad for eight weeks. Returning to London towards the end of June, I saw for the first time F. H.'s second article. My object is not to make points against him, but to throw more light upon the question.

1. Whatever F. H. thinks of the evidence adduced by Desbrière, he will admit that Napoleon's officers were never able to get more than 100 ships out of Boulogne Harbour in one tide, that except in the narrow space formed by the channel of the Liane the ships were generally aground, and that not only lack of room but also the force of the tidal current was a serious obstacle.​2 F. H. says that 'in any case this evidence yields only probabilities.' I never contended that it yielded more. But since Caesar had to get at least 600‑650 ships out of Portus Itius, not merely in one tide but in two hours or less, or else to start from the roadstead outside the harbour, the probabilities can hardly be ignored.

2. F. H. affirms that 'no ground exists for alleging that the other 150 or 200 trading ships' — the ships which sui quisque commodi causa fecerat — 'all started from . . . any particular spot.' It seems to me that two grounds exist for supposing that they started from Portus Itius. First, if they started from any other port, they and their owners needed special protection; and since Caesar allowed the owners to accompany him, if he had forbidden them to start from Portus Itius, he would surely have detached troops to protect them. Secondly, the 'trading ships,' the transports, and the galleys were all visible off the British coast at the same time.​3 Is it not probable that they all started from the same port? At all events no ground exists for alleging that the 'trading ships' started from a port other than Portus Itius. Nevertheless, I will make F. H. a present of them.

3. The 'nautical opinion' did not mean 'that the ships could be got out with a depth and extent of water which might be reasonably assumed': it meant that they might have been got out with the depth and extent of water which Desjardins postulated. Desjardins's plan​4 represents the mouth of the harbour as about 530 yards wide. Probably it was; but one may doubt whether at the time when the ships began to move — about four hours before high water​5 — it was deep enough near the sides to float them.​6 The sides of estuaries which have not been artificially improved are dry at low water. The 'nautical opinion' was based on the hypothesis that the ships did not start from the wharves, but that, after leaving the wharves, they were anchored in parallel rows in the estuary, and were ready ad solis occasum  p194 to start in the order which would have enabled the rowers to clear the harbour in the shortest possible time. To assume that when they were about to start they were at anchor strains the words naves soluit. It is permissible to suppose that the ships started from the wharves, where the troops had embarked, close to the camp. Of the whole fleet about 540 transports and 28 galleys could be rowed.​7 If they had been drawn up in single file, 570, placed end of the end in actual contact, would have formed a line nearly 7 miles long.​8 Therefore, if Portus Itius was Boulogne, we must suppose that they were massed like Napoleon's ships, alongside the wharves in contiguous rows, say eight or nine deep;​9 or, if there were two camps, one on either side of the harbour, four or five deep. The harbour-master of Dover believes that they could not have been rowed out against the tide at the rate of more than two miles an hour.​10 I have calculated that with perfect organization and supposing that the rowers had worked with machine-like precision, that the current had not interfered with steering, and that there was room for ten ships to move out abreast, the ships might have cleared the harbour in four hours, or, if they started simultaneously from wharves on either side, in two.​11 Perhaps, if they had been formed side by side perpendicularly to the wharves, the time might have been reduced; but I am not sure that in this case they would not have been unduly crowded.

But the ships that could be rowed were not the whole fleet. Neither the 'nautical opinion' nor the calculation which I have just mentioned took account of the larger ships which Caesar had used in the previous year. Most of these ships, however, were used again in 54 B.C.​12 They could not have cleared the harbour along with the others: they must have started either before or after;​13 and, if they had started from the wharves, to get them out under sail would have taken a long time. The small fleet — eighty transports and a few galleys — which sailed from Boulogne in 55 B.C. was inconveniently strung out.​14 If the whole fleet started in the order required by the 'nautical opinion,' it may have cleared the estuary in two hours; but one must not forget what Napoleon's harbour-master said about the tide: 'La vitesse est telle pendant près de deux heures dans les grandes marées, que l'art et la précaution de la manoeuvre ne peuvent en triompher.'​15 It is true that the period during which the tide flowed at this speed did not begin till about two hours and a half before high water; but while it lasted Napoleon's officers could not get their ships out at all. Some may be inclined to suppose that Caesar's ships, having cleared the harbour in the course of the day, started ad solis occasum from the roadstead; but this assumption also strains the meaning of naves soluit. Perhaps the words will bear the strain;​16 but the difficulty must be faced.

4. I of course admit that, as F. H. says, 'it is doubtful whether' the Earl of Leicester 'originally sailed from Wissant with a very large force.'

5. F. H. says that 'on any ordinary calculation the supply [of water] mentioned by Mr. Holmes would not have sufficed for the animals alone, even if — as is impossible — not a drop had been  p195 wasted.' In the Crimean War 'every gallon of water that the spring gave was made available.' If F. H. will consult The Soldier's Pocket-Book,​17 he will see how simple was the well-known contrivance by which this result was attained. He will be quite safe if he accepts the calculation of Lord Wolseley, — that a horse 'requires from six to eight gallons per diem' and a mule six gallons.​18 Besides the 4,000 cavalry horses, there were, according to the usual estimate, 4,000‑4,800 beasts of burden, and, let us say, 1,000 cavalry remounts. I will suppose that 10,000 horses and mules had to be provided for. They would have required 60,000 gallons a day. My informant, speaking with authority, stated that there were ' entr'autres trois sources extrèmement abondantes. ' He gave the daily yield of two of the three, — 80,000 + 200,000–300,000 litres. Taking the mean between the two latter figures, we get a total of 330,000 litres, or 73,260 gallons. This would have provided for the animals and have left for the men about 13,000 gallons, plus the supply yielded by the other springs, one of which is 'extrèmement abondante.' F. H. reckons that there were 39,000 men to be provided for, besides the crews and 'a miscellaneous host of camp-followers,' whose numbers he will not conjecture. The crews, except those of the twenty-eight galleys, did not include rowers; for the transports were rowed by soldiers.​19 Let us suppose that the crews numbered 3,000.​20 The 'camp-followers' were the mercatores, who followed the army in order to trade with it, and were not allowed to sleep inside the camp, and the calones, — slaves who performed menial duties and drivers. We may be sure that Caesar kept the number of the former within bounds, and that of the latter he employed no more than were necessary. I can discover only one indication of their relative numbers under the Republic. It will be found in Bell. Civ., III.2.2, compared with 6.1‑2. In the former passage Caesar says that when he reached Brundisium in the autumn of 49 B.C. he found only enough ships to carry 15,000 legionaries and 600 cavalry. In 6.1‑2 he says that he urged the men, who cheerfully consented, to leave behind the slaves and heavy baggage (mancipia atque impedimenta), in order to provide room for more troops, and that he sailed with seven legions [and 600 cavalry]. The seven legions amounted, as Stoffel​21 calculates, to about 20,000 men. We may infer that the slaves and baggage — that is, all the baggage that could be dispensed with — of 15,000 legionaries and 600 cavalry took up as much room as 5,000 legionaries. The impedimenta presumably included the beasts that would have carried the superfluous baggage. The slaves therefore evidently numbered less than 5,000; and if I assume that there were 2,000 'camp-followers' at Portus Itius, I shall perhaps be making an excessive estimate. In the field every man requires six pints of water a day for drinking and cooking, and, as Lord Wolseley says, 'a similar amount will just allow men to wash their bodies.'​22 Thus 54,000 men would have required 81,000 gallons. Though the third 'abundant' spring and the others would probably not have supplied the needful amount, there were other sources, — the river Slacq, which was not more than four miles from any spot where the army would have encamped near Wissant, and its tributary, the Bazinghen, which was rather nearer. The animals needed exercise and could well have been taken thither to water, leaving the springs for the men.​23 'It is a good plan,' says Lord Wolseley, 'to water when about one or two miles from camp, and then to walk the horses slowly to their lines for the night: always give lake or river water [to animals] in preference to that from springs or wells.'​24 Even at Boulogne it would have been necessary to go some miles up the Liane for fresh water, unless  p196 springs yielded enough, for in the estuary the water was of course brackish.

F. H. tells me that I 'observed (Ancient Britain, p583) that Caesar's forces could not possibly have been fed at Wissant.' Neither on p583 nor anywhere else. What I said (on p584) was that 'to transport [food] to Wissant without roads would have been a task of extreme difficulty,' — for wagons. As I did not then realise that Caesar may have thought it advisable to discard Boulogne in 54 B.C., lest he should be unable to clear the estuary in a reasonable time, I naturally argued that he would have preferred the port which was connected with the interior by roads to one which, as far as we know, was not. But, if he desired to avoid the difficulties of extricating his huge fleet from the estuary, it was not difficult to transport grain to Wissant on pack-horses; and, as I now know, if the ground is firm, even wagons can be drawn by oxen where there are no roads.​25 It must not be forgotten that Caesar did not intend to stay long at Portus Itius: the north-westerly winds which delayed him for twenty-five days were unexpected and unusual.

I have only tried to show that the case for Boulogne cannot be regarded as conclusively proved. There is reason, I repeat, to believe that between Cape Gris-Nezº and Cape Blanc-Nez the ships which were constructed with a view to their being easily hauled up on shore could have remained above the high-water mark of spring tides, while the older vessels might have ridden in the anchorage which is protected against northerly and north-westerly winds by a sandbank, and against south-westerly winds, to some extent, by Cape Gris-Nez;​26 it was possible to feed the troops; and there was enough water. I think therefore that F. H. exaggerates when he says that 'the evidence is dead against Wissant'; and I hope to convince him that the weakness, or the element of doubt, which I have discovered in the case for Boulogne is not imaginary.

T. Rice Holmes.

[By the courtesy of the editors I have seen a proof of the above. Plainly, the controversy, if it is not to swallow the whole Classical Review, must stop here, before the multitudes of 'ifs' get thicker. I will say only, as to water at Wissant, that I took expert military counsel before I wrote, and that Mr. Holmes seems to have minimised his men and beasts and their need beyond due measure, and yet not to have enough water. For the rest, I must console myself that, if I am not on the same side as Mr. Holmes, I am on the side of M. Jullian. — F. H.]

---

The Author's Notes:

1 Classical Review, December, 1913; March and May, 1914.

2 E. Desbrière, Projets et tentatives, etc., III.144, 147‑8, 451, 566; IV.145, 395, 398.

3 B. G., V.8.6.

4 Géogr. de la Gaule rom., vol. I, pl. XV and XVII.

5 Ancient Britain, pp729‑30. In Ancient Britain (p576, n1) I was obliged to assume that ad solis occasum meant about 7 P.M., — an hour before sunset; otherwise there would hardly have been time for the ships to get from Boulogne to the point which they reached at dawn. The assumption was, I think, permissible; if not, the case for Boulogne is weakened.

6 In the Bronze Age the bed of the estuary in the 'ancien bassin,' which in the Stone Age had been considerably deeper, was 8 m 24 (about 27 feet) below the level of high water at spring tides. See Boulogne-sur‑mer et la régionº boulonnaise, I, 1899, pp23‑4, and cf. Desjardins, I.380. But at Boulogne the range of spring tides is 25¼ feet (The Channel Pilot, Part II, 1906, p559).

7 B. G., V.2.2; 5.2.

8 The transports could hardly have been smaller than Napoleon's smallest vessels, which were •60 feet long. See Caesar's Conquest of Gaul, p436, n6, and B. G., V.23.5.

9 See the plan in Desbrière's fourth vol., p400.

10 So he told me in 1911.

11 The best plan would have been this. Suppose that ships in the column furthest from the wharf, reckoned from the ship nearest the mouth of the harbour, were numbered 1, 2, 3 . . . The crews of 10, 20, 30, etc., would have simultaneously cast off the hawsers, and begun to row diagonally across the stream. At the right moment 9, 19, 29, etc., would have followed suit. Thus ultimately 10, 9, 8 . . . 1 would have been rowing abreast, followed by 20, 19, 18, etc. Then the next column would have begun to move, and so on. Remember that the current was of course strongest in mid-stream, and that there are eddies at the mouth of the harbour.

12 B. G., V.1.1.

13 Probably after; for their draught was greater, and when the transports had gone there would have been more water.

14 Cf. B. G., IV.23.2 with § 4.

15 Desbrière, III.144.

16 See Caesar's Conquest of Gaul, 1911, pp456, 438.

17 Fifth ed., 1886, p258.

18 The Soldier's Pocket-Book, 1886, pp73, 77.

19 B. G., V.8.4.

20 The author of the 'nautical opinion' owns a ketch, •57 feet long, which he sails with the help of two men.

21 Hist. de Jules César, II.323.

22 The Soldier's Pocket-Book, p95.

23 At Alexandria Caesar sunk wells with satisfactory results (Bell. Alex. 8.1; 9.1‑2); but to do so at Wissant would have been unnecessary.

24 The Soldier's Pocket-Book, p73.

25 The Soldier's Pocket-Book, p78.

26 Cf. Desbrière, III.162, with Geol. Mag., 1866, pp113‑4.

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