1st Infantry Brigade, under General Buller: Royal Engineers, 62 men; 3rd Battalion King's Own Rifles, 565 men; Gordon Highlanders (75th), 712 men; Royal Irish Fusiliers (89th), 343 men.
2nd Infantry Brigade, under General Davis: Royal Highlanders (42nd Black Watch), 623 men[99]; York and Lancaster (65th), 435 men; Royal Marine Artillery and Light Infantry, 478 men.
At daybreak on the 12th the cavalry, comprised of 251 men of the 10th Hussars, 362 men of the 19th Hussars, and 124 of the Mounted Infantry, arrived at the zeriba, where the total force now amounted to 4,069 men.
About 10 a.m. it was reported that the enemy was in force some six miles distant. Accordingly, the troops were ordered to advance towards Tamaai as soon as the men had had their dinners. About 1 p.m. the force began to move.
The following diagram explains the formation:—
The 1st Brigade, under Buller, marched on the right rear of the other, at a distance varying from 600 to 900 yards in an oblique line. In military language the two brigades moved in echelon, the 2nd Brigade leading, the object being to expose the enemy, in the event of his charging one brigade, to a raking or flank fire from the other. The rear battalions and the half-battalions on either flank of each brigade marched at wheeling distances, so that on the word to form outwards being given, two complete squares could be formed. The two brigades were thus placed so as to form two independent oblongs, the front face or line of each brigade being about 200 yards in length, the sides about 100 yards. The main body of the cavalry was echeloned on the left rear of the 2nd Brigade.
It will be seen that, although the force at Tamaai was about the same as that at El-Teb, a different formation was adopted. The unwieldiness of a single great square had been shown by experience. It had the further disadvantage that, in the event of an attack on one side, the fire of at least two of the other sides could not be utilized. There was, moreover, the old adage against "putting all one's eggs in one basket." The comparatively difficult ground which had to be got over at Tamaai was probably another reason for the change.
The line of march was about south-west. The Mounted Infantry having reported that the low hills, six miles in front, were clear of the enemy, it was deemed advisable to gain and occupy them before dark, and, if possible, attack the enemy and drive them from their position near the wells. The afternoon was hot, and frequent halts were necessary. The ground was covered with grass knee-deep, scrub and brushwood, and in some places the prickly mimosa and cactus were seven feet high.
By 3.30 the highest hill of the range was reached by the cavalry scouts, and the broad intervening valley of Tamaai could be seen from its summit through the haze. About four o'clock the infantry squares reached the base of the hill and halted for a few minutes, whilst the scouts were pushed forwards. At five o'clock they came in and reported that the enemy, estimated at 4,000 men, were advancing to the attack.