The Duke of Athole immediately wrote to Lieutenant-General Carpenter, who had succeeded John, Duke of Argyle and Greenwich, as Commander-in-Chief in Scotland (the general was also Governor of Minorca), informing him that he had "captured Robert MacGregor Campbell, the famous outlaw and rebel, for whose apprehension a large sum had been so long offered by the authorities."

He requested the general to send from Edinburgh a body of troops to escort the prisoner to that city, and, in compliance with his wish, a troop of Lord Polwarth's Scottish Light Horse (now the 7th Hussars), marched so far as Kinross.

Meanwhile, the unfortunate MacGregor was kept a close prisoner, manacled with cords, and guarded day and night by the vassals of the duke, and a party of Captain MacDougal's Horse Grenadiers, whom he had obtained from the officer commanding in Perth.

In a short time it was known all over Scotland that Rob Roy was a captive; but the mode of his capture, and the foul treachery which characterized it, covered Athole with disgrace, though he seems to have felt no small vanity at the success of his snare, if we may judge from a letter which he wrote to John, Duke of Roxburgh, who was Secretary of State for North Britain, minutely detailing the affair.

Panting for freedom and for vengeance, both of which were justly his, Rob Roy was kept under the military escort at a place called Logierait, which lies eight miles north of Dunkeld; there he had been conveyed after his capture in the castle of Blair.

It was a dark and boisterous night when the troops began their march from the latter place, with the prisoner still bound and tied to a horse; a horse grenadier with his unslung carbine riding on each side of him. The clouds were driven in black masses along the summits of Ben-ghlo and Cairn-na-Gabar (or the mountain of the goats), and the roaring wind rolled over the thick old forests of Blair Athole, bowing the trees till their masses seemed to heave like the waves of the sea, in the fitful gleams of the moon. On halting at Logierait, the duke ordered MacGregor to be kept there securely, until a properly-mounted escort of his own people was in readiness to convey him to Edinburgh. The duke was resolved that the whole merit of the capture should remain with himself, and that even the king's troops should not share it.

But this vanity proved in the end his own defeat.

Rob Roy, on finding himself in one of the miserable cottages of the village, began to hope that he might perhaps achieve an escape. As a preliminary, he begged the sergeant who commanded the troopers, to undo the cords which bound his hands, that he might write a farewell letter to his unhappy wife, who had then found shelter in the little farmhouse of Portnellan, at the head of Loch Katrine.

The sergeant was a humane man; he said something about his own wife and little ones who were far away in old Ireland, and he did as Rob requested, though in defiance of express orders.

Then, as he had been liberal in supplying the soldiers with whisky and ale, they became friendly with MacGregor, and so, after a time, the letter was written; but there was a difficulty in procuring a messenger to Loch Katrine, as several MacGregors had located themselves thereabout, and reprisals were dreaded.