Close connection between Boer main army in Natal and Botha.
Botha's detachment and the Boer main army were, however, within an hour's ride of each other, and thus could readily render mutual assistance, unless an attack from the south should be combined with an exactly-timed sortie by the Ladysmith garrison. Yet the Boers had reason to fear this combination against them. The troops under Sir George White were still mobile, and the enterprises against Gun Hill and Surprise Hill, in the second week of December, had shown that both officers and men were keen to be again let slip at the enemy.[216] Moreover, the large number of mounted men, who, though shut up in Ladysmith, were in fact astride of the Boers' lines of communication, both with the Transvaal and with the Free State, would be likely to prove a serious danger in the event of Botha's defeat by Sir Redvers.
A formidable natural fortress.
Nevertheless, the task which the British commander-in-chief had decided to undertake was not an easy one. From Potgieters Drift on the west to the junction of the Tugela with Sunday's river, about 30 miles east of Colenso, a ridge of hills, broken only by narrow kloofs and dongas, line like a continuous parapet the northern bank of the former river. Westward the ridge is connected by the Brakfontein Nek with that spur of the Drakensberg which is entitled the Tabanyama Range. This was destined, a month later, to bar the advance of the relieving army on that side. The eastern flank was guarded by the lower slopes of the Biggarsberg, which run parallel to Sunday's river and fill the area lying between that stream and the Buffalo. The approaches to the beleaguered town from the south were thus covered by an immense natural redoubt. Opposite to the very centre of the front face of this redoubt lay Colenso. Behind this centre, and at right angles to the parapet, a cluster of hills was flung back to the ridge of Cæsar's Camp, immediately to the south of Ladysmith. Through this confused mass of broken ground, so favourable to the methods of fighting of its defenders, ran the three roads which connect Colenso and Ladysmith. Of these roads the western passed over three very strong and presumably entrenched positions. The central had become by disuse impassable.[217] Much of the eastern was only fit for ox-wagons. Along the face of this strategic fort ran the Tugela, an admirable moat, as completely commanded by the heights on its left bank as is the ditch of a permanent work by its parapet. West of Colenso this moat was traversable by guns and wagons at only five places, i.e., Robinson's, Munger's, Skiet's, Maritz, and Potgieters drifts. Of these the four first named were difficult for loaded wagons. Eastward of Colenso the only practicable drift was that by which the Weenen road crosses the river. Other fords, through which single horsemen or men on foot, breast-high, could wade, existed both to the east and to the west, but with the exception of a bridle drift near Colenso they were not marked on the maps in possession of the troops, and could only be discovered by enquiry and reconnaissance.
Botha depends on mobility for holding his long line of defence.
The commandos assigned to General Louis Botha for the defence of the line of the Tugela were obviously insufficient to man the whole of this immense position; yet he was able to rely on the mobility of his burghers; and on this, also, that he was so situated that his assailant would, in order to attack him anywhere, have to traverse distances greater than Botha need cover to reinforce from the centre either flank as soon as threatened. Moreover, not only did the heights he held afford a perfect view for miles over the country to the south, but the Tugela hills are precipitous and rocky as to their southern faces, while the approaches to them from the north present, as a rule, easy slopes and gentle gradients.
Difficulty of finding out where the Boers were.
In ascertaining the exact localities occupied by the enemy, Sir Redvers Buller was handicapped by many circumstances. A considerable space along the river could in the daytime only be approached by reconnoitrers under the close view and fire of the picked riflemen of the veld. The whole of the original Intelligence staff and the subordinate personnel of scouts and guides, organised for the Natal Field Force before the outbreak of the war, had been left locked up with the troops in Ladysmith. The nucleus of a fresh Intelligence staff had, however, been started by 2nd Lieut. A. N. Campbell, R.A., and was subsequently taken over by Mr. T. K. Murray, C.M.G., after the disbandment of his corps of scouts. The reports of Mr. Murray, who was subsequently created a K.C.M.G. for his services, as well as information sent out by runners, heliograph, and pigeon post from Ladysmith, agreed that the main body of Botha's force was concentrated immediately in front of Colenso. A reconnaissance, suggested by a Ladysmith message, dated 17th November, had been conducted by Captain H. De la P. Gough towards Potgieters drift on the 29th November, but had failed to get touch with the enemy. Intelligence scouts had, however, reported the Boer commandos at Potgieters and Skiet's drifts, and it was also known that Boer patrols were watching the intermediate crossings. It might therefore be assumed that the whole line of the river was kept under Boer observation.
It will be seen that the topographical conditions, though not at the time fully known, made it impossible to turn either flank of the great crescent of hills which barred an advance on Ladysmith. On the other hand, it seemed probable that a sudden march, eastward or westward, would find some passage of the river, and of the natural parapet beyond, unentrenched and but slightly guarded. An examination of the map, and a study of the country to the eastward, showed that a flank movement in that direction would be compelled to follow a circuitous route, and to traverse broken ground, covered with bush and exceedingly favourable to ambuscade and to surprise attacks. Sir Redvers judged that to commit troops, untrained to manœuvre over terrain of this description and hampered by many ox-wagons, to a rather long flank march in presence of a mobile enemy, would be too dangerous an enterprise. Moreover, the ground to the east was unfavourable for any sortie from Ladysmith, and in a telegram dated the 30th November, Sir George White had definitely reported that he could give most help to the relieving force if it advanced viâ Onderbrook Spruit (i.e., by the western of the two possible Colenso-Ladysmith roads) or viâ Springfield and Potgieters drift.
Sir Redvers' view of the choice open to him.