The interview ended by Mahony retiring to the town, agreeing to send back an answer in half an hour.

At the end of that time he sent out a capitulation by a Spanish officer.
Had Peterborough's scheme ended here he would not have exceeded the bounds of what is regarded as a fair method of deceiving an enemy, but his subsequent proceedings were absolutely indefensible, and are, indeed, almost incredible on the part of the man who in some respects carried the point of honor almost to an extreme.

His notion, no doubt, was to paralyze the action of the enemy by exciting suspicions of treachery among their leaders, but the means which he took to do so were base and unworthy in the extreme.
He began with the Spanish officer who had brought the capitulation, giving him a garbled account of his interview with Mahony, and then endeavoring to bribe him to desert to the Austrian cause, insinuating that he had succeeded by this means with Mahony.

As the earl expected, he failed to induce the Spaniard to desert, but he succeeded in his purpose of filling his mind with suspicions of treachery on the part of Mahony.
Mahony had conducted the negotiations in a manner worthy of a loyal and skillful officer; he had stipulated not to leave the town till one o'clock in the morning, and that Peterborough should not pass the river until that hour.
This he had arranged in order to allow the Duke of Arcos time to reach the plains, where he was to be joined by the horse from Murviedro.

But Peterborough's machinations had been effectual; the Spanish officer, on his return, informed his countrymen that Mahony had betrayed them, and the troops and populace became enraged against the unfortunate Irishman and threatened his life.