It was only over tracts where he considered that devastation would hamper the movements of an English army, that everything was laid waste.
"On the 21st of August he invested Arcot, and a week later, hearing that the British army had moved out from Madras, he broke up the siege and advanced to meet them.

Sir Hector Munro, the British general, was no doubt brave, but he committed a terrible blunder.

Instead of marching to combine his force with that of Colonel Baillie, who was coming down from Guntoor, he marched in the opposite direction to Conjeveram, sending word to Colonel Baillie to follow him.

Baillie's force amounted to over two thousand eight hundred men, Munro's to five thousand two hundred.

Had they united, the force would have exceeded eight thousand, and could have given battle to Hyder's immense army with fair hope of success.