Lord George marched with unheard of dispatch towards Atholl. Already had the Duke of Cumberland placed at different parts, in that district, bands of the Argyleshire Campbells, to the amount of three hundred in number. A thousand more, it was reported, were coming from the same quarter; and it was Lord George's aim to intercept this reinforcement. He set off, followed by his brave "Atholl-men," conducting his march through byeways across the mountains; and in one march, day and night, he traversed a tract of thirty miles. It was, however, impossible to transport cannon through these almost impassable solitudes; yet, with a force not exceeding seven hundred men, Lord George contrived to surprise the enemy at these posts. He entered Atholl in the early part of the night; his detachment then separated, and, dividing itself into small parties, each gentleman whose home had been invaded took the shortest road to his own house. The English soldiers were surprised in their sleep, and, according to the Chevalier Johnstone, lay murdered in their beds; but this is contradicted by many authorities.[174] These Highland gentlemen attacked, during that night, thirty of the posts in question, and all of them were carried. Few of the Government troops were put to the sword; about three hundred were taken prisoners, and between two and three hundred barricaded themselves in the Castle of Blair.[175]
The Marquis of Tullibardine had, it appears, been driven from that fortress some time previously. Misfortune was not new to one who had joined in the insurrection of 1715.
"As the late Rothiemurcus,[176] your father," he writes to a friend,[177] in a letter to which he dared not even state his place of residence, "showed me particular friendship and kindness on just such an unfortunate occasion as the present, makes me hope you will have no less regard for me in taking care of some small concerns of mine; which consists in taking care of two of three of my servants and some baggage, which I send you, rather than it should fall into enemies' hands; so that if you cannot keep it, and get it sent me in time and place convenient, it may be of some use to yourself, whom I esteem on your family and father's account; though we have not had the occasion of a personal acquaintance, which I hope may yet agreeably happen, in whatever bad situation our affairs may at present appear; then I may agreeably be able to return you suitable thanks for such an obligation as will for ever oblige,
"Sir,
"Your affectionate humble servant and cousin,
"Atholl."
14th March, 1746.
The Clan of Atholl was the largest that engaged in Prince Charles's service, and numbered nearly fifteen hundred men. Lord George now collected three hundred more of these vassals, and invested Blair Castle. One difficulty he had in the deficiency of cannon; he obtained, however, some field-pieces from Inverness, but his artillery was too light to make an impression on the walls. There was an alternative, which was, to reduce the castle by famine. Blair, as it happened, was defended by a stout and sturdy veteran, Sir Andrew Agnew, who was resolved only to yield upon extreme necessity his important charge. During the siege, Lord George wrote on the subject of the enterprise to his brother the Marquis of Tullibardine. The letter was answered in a manner which shows that some want of candour had been evinced towards the Marquis, who was regarded by all the Jacobites as the legitimate owner of Blair. The epistle breathes the tone of mournful resentment. "Since, contrary to the rules of right reason, you have been pleased to tell me a sham story about the expedition to Blair," such are the expressions used by the Marquis of Tullibardine, "you may now do what the gentlemen of that country wish with the castle."[178] With the true value of a high-born man for the memorials of his ancestors, the Marquis grieved most for the loss of his great-great-grandfather's grandfather's, and father's pictures. "They will be ane irreparable loss." But every thing that could promote the public service was to be resigned cheerfully and willingly for that cause. Not only did he proffer the sacrifice of his castle, but he pointed out to his brother a gate which had formerly been a portcullis, leading into it. This was at that time half-built up, and boarded, with a hollow large enough to hold a horse at rack and manger; and the Marquis suggested that this place might be more easily penetrated than any other part of the wall, so as to make an entrance into the vaulted room called "the Servants' Hall."
Whether or not Lord George decided to take advantage of this hint is unknown. The attack made upon the Castle of Blair was conducted by him in person, and was begun simultaneously with those headed by his followers upon the various posts at Blairfitty, Kinachie side, and several places near Blair. Upon the persons of the prisoners were found copies of their orders from the Duke of Cumberland, and these were signed by Colonel Campbell, and contained instructions to attack the rebels wherever they should meet them; and in case of resistance, it was the Duke's orders that they should get no quarter.[179] Stimulated by these intercepted documents, Lord George, early on the morning of the eighteenth of March, began the siege of Blair.
Many have been the accounts given, and various are the surmises upon the motives of Lord George in not reducing the castle; but in estimating the real difficulties of his undertaking, the testimony of a soldier and a contemporary must be taken in evidence.
Blair was defended by a man of no ordinary character, Sir Andrew Agnew, Lieutenant-Colonel of the Royal North British Fusiliers, who had been sent with a detachment from Perth by the route of Dunkeld, through the pass of Killicrankie, to take possession of the Castle.