Meanwhile, since doubts were felt as to the main operation of storming the new breach, No. III, subsidiary efforts were made to incommode the enemy in other ways. At intervals on the 9th, 10th, and 11th red-hot shot were fired at the church of Santa Maria la Blanca, where it was known that the French magazine of food lay. The experience of the Salamanca forts had led the artillery officers to think that a general conflagration might be caused. But the plan had no success; the building proved to be very incombustible, and one or two small fires which burst out were easily extinguished. Another device was to mine out from the end houses of the city towards the church of San Roman, an isolated structure lying close under the south-east side of the Castle, which the French held as an outwork. Nothing very decisive could be hoped from its capture, as if taken it could only serve as a base for operations against the two enceintes above it[52]. But, as an eye-witness remarked, at this period of the siege any sort of irregular scheme was tried, on the off chance of success. By October 17 the mine had got well under the little church. A more feasible plan, which might have done some good if it had succeeded, was to run out a small mine or fougasse from the sap-head of the trench in front of breach I to the palisades of the second enceinte. It was a petty business, no more than two barrels of powder being used, and only slightly damaged an angle of the work in front when fired on October 17. An attempt to push on the sap after the explosion was frustrated by the musketry fire of the besieged.
On the 18th the engineers reported that the church of San Roman was completely undermined, and could be blown up at any moment. On the same morning the one good and two lame 18-pounders in battery 2 on San Miguel swept away, not for the first time, the sandbag parapets and chevaux de frise with which the French had strengthened the breach III. They were then turned against the third enceinte, immediately behind that breach, partly demolished its ‘fraises,’ and even did some damage to its rampart. This was as much as could have been expected, as the whole of the enemy’s guns were, as usual, turned upon the battering-guns, and presently obtained the mastery over them, blowing up an expense-magazine in No. 2, and injuring a gun in No. 1. But in the afternoon the defences were in a more battered condition than usual, and Wellington resolved to make his last attempt. Already the French army outside was showing signs of activity; and, as a precaution, some of the investing troops—two brigades of the 6th Division—had been sent forward to join the covering army. If this assault failed, the siege would have to be given up, or at the best turned into a blockade.
The plan of the assault was drawn up by Wellington himself, who dictated the details to his military secretary, Fitzroy Somerset, in three successive sections, after inspecting from the nearest possible point each of the three fronts which he intended to attack[53].
Stated shortly the plan was as follows:
(1) At 4.30 the mine at San Roman was to be fired, and the ruins of the church seized by Brown’s caçadores (9th battalion), supported by a Spanish regiment (1st of Asturias) lent by Castaños. A brigade of the 6th Division was to be ready in the streets behind, to support the assault, if its effect looked promising, i.e. if the results of the explosion should injure the enceinte behind, or should so drive the enemy from it that an escalade became possible.
(2) The detachments of the Guards’ brigade of the 1st Division, who were that day in charge of the trenches within the captured outer enceinte, and facing the west front of the second enceinte, were to make an attempt to escalade that line of defence, at the point where most of its palisades had been destroyed, opposite and above the original breach No. I in the lower enceinte.
(3) The detachments of the German brigade of the 1st Division, who were to take charge of the trenches for the evening in succession to the Guards, were to attempt to storm the breach III in the re-entering angle, the only point where there was an actual opening prepared into the inner defences.
From all the works, both those on St. Miguel and those to the west of the Castle, marksmen left in the trenches were to keep up as hot a musketry fire as possible on any of the enemy who should show themselves, so as to distract their attention from the stormers.
The most notable point in these instructions was the small number of men devoted to the two serious attacks. Provision was made for the use of 300 men only in the attack to be made by the Guards: they were to move forward in successive rushes—the first or forlorn hope consisting of an officer and twenty men, the supports or main assaulting force, of small parties of 40 or 50 men, each of which was to come forward only when the one in front of it had reached a given point in its advance. Similarly the German Legion’s assault was to be led by a forlorn hope of 20, supported by 50 more, who were only to move when their predecessors had reached the lip of the breach, and by a reserve of 200 who were to charge out of the trench only when the support was well established on the rampart.
Burgoyne, the senior engineer present, tells us that he protested all through the siege, at each successive assault, against the paucity of the numbers employed, saying that the forlorn hope had, in fact, to take the work by itself, since they had no close and strong column in immediate support; and if the forlorn hope failed, ‘the next party, who from behind their cover have seen them bayoneted, are expected to valiantly jump up and proceed to be served in the same way.’ He reminded Wellington, as he says, that the garrison at Burgos was as large as that at Ciudad Rodrigo, where two whole divisions instead of 500 or 600 men had been thrown into the assault. The Commander-in-Chief, condescending to argument for once, replied, ‘why expose more men than can ascend the ladders [as at the Guards’ attack] or enter the work [as at the breach in the K.G.L. attack] at one time, when by this mode the support is ordered to be up in time to follow the tail of the preceding party[54]?’ And his objection to the engineer’s plea was clinched by the dictum, ‘if we fail we can’t lose many men.’ This controversy originally arose on the details of the abortive storm of September 22, but Burgoyne’s criticism was even more convincing for the details of the final assault on October 18. The number of men risked was far too small for the task that was set them.