The trenches made ground daily, but one last formidable obstacle prevented their approach close enough to the city for the siege guns to begin their destructive work. On the southern bank of the Cauvery, a half-mile west of the city, stood the ruins of an old watermill. Built of stone, the ancient walls were thick enough to withstand the artillery fire from Harris’s camp and from the new British positions across the river. The ruined buildings had been converted into a stout fort that was equipped with a deep defensive ditch and was strongly garrisoned by two of the Tippoo’s finest cushoons, reinforced by cannon and rocketmen, and so long as the mill fort existed no British gun could be dragged within battering range of the city’s walls. The two flags that flew over the mill fort were shot away every day, but each dawn the flags would be hoisted again, albeit on shorter staffs, and once again the British and Indian gunners would blaze away with round shot and shell, and once again the sun flag and the banner of the
Lion of God would be felled, but whenever skirmishers went close to the fort to discover if any defender survived, there would be a blast of cannon, rockets and musketry to prove that the Tippoo’s men were still dangerous. The Tippoo could even reinforce the garrison thanks to a deep trench that ran close to the south branch of the Cauvery and up which his men could creep through the night to relieve the fort’s battered garrison.
The fort had to be taken. Harris ordered a dusk attack that was led by Indian and Scottish flank companies supported by a party of engineers whose job was to bridge the mill’s deep ditch. For an hour before the assault the artillery on both banks of the river rained shells into the mill. The twelve-pounder guns were loaded with howitzer shells and the wispy trails of their burning fuses sputtered across the darkening sky to plunge into the smoke which churned up from the battered fort. To the waiting infantry who would have to wade through the Little Cauvery, cross the ditch and assault the mill it seemed as if the small fort was being obliterated, for there was nothing to be seen but the boiling smoke and dust amongst which the shells exploded with dull red flashes, but every few moments, as if to belie the destruction that seemed so complete, an Indian gun would flash back its response and a round shot would scream across the fields towards the British batteries. Or else a rocket would flare up from the defenders and snake its thicker smoke trail across the delicate tracery left by the fuses of the howitzer shells. The largest guns on the city wall were also firing, trying to bounce their shot up from the ground so that the ricochets would reach the besiegers’ artillery. Sharpe, inside the city, heard the vast hammering of the guns and wondered if it presaged an assault on the city’s walls, but Sergeant Rothiere assured the men that it was only the British wasting ammunition on the old mill.
The bombardment suddenly ceased and the Tippoo’s men
came scrambling out of the mill’s damp cellars to take their places at their fire-scorched ramparts. They reached their broken firesteps just in time, for the leading engineers were already hurling lit carcasses into the ditch. The carcasses were bundles of damp straw tight wrapped about a paper-cased shell of saltpetre, corned gunpowder and antimony. The carcasses burned fiercely, consuming the straw from the inside to billow choking streams of smoke through vents left in the casings so that within seconds the ditch was filled with a dense fog of grey smoke into which the frightened defenders poured a badly aimed musket volley. More carcasses were hurled, adding to the blinding smoke, and under this cover a dozen planks were thrown across the ditch and screaming attackers charged across with fixed bayonets. Only a few of the Tippoo’s men still had loaded muskets. Those men fired, and one of the attackers fell through the smoke to fall on the hissing carcasses, but the rest were already scrambling over the walls. Half the attackers were Macleod’s Highlanders from Perthshire, the others were Bengali infantry, and both came into the mill like avenging furies. The Tippoo’s men seemed stunned by the suddenness of the assault, or else they had been so shaken by the shelling and were so confused by the choking smoke that they were incapable of resistance, and incapable, too, of surrender. Bengalis and Highlanders hunted through the ruins, their war cries shrill as they bayoneted and shot the garrison, while behind them, before the smoke of the carcasses had even begun to fade or the fighting in the mill die down, the engineers were constructing a stouter bridge across which they could haul their siege guns so they could turn the old mill into a breaching battery.