The Earl of Mar was at that time in Paris, and Lord Carteret who was at the head of affairs in England, remembering the Earl's former negotiations with Lord Stair, dispatched a gentleman to Mar, with instructions to sound that nobleman as to his knowledge of the plot. Lord Mar happening to be in Colonel Dillon's company when the messenger reached Paris, and soon divining after one interview the nature of the embassy, it was agreed between him and Dillon that they would do James's cause a service by leading the British Government off the right scent. They therefore drew up, in conjunction, an answer to Lord Carteret. What was the nature of that reply,[168] does not appear; but its result was such as to cast upon Lord Mar a degree of odium far greater than that which he had incurred in Lord Stair's business. He was accused by Atterbury with having, on that occasion, written such a letter as had been the cause of his banishment; with having betrayed the secrets of the Chevalier St. George to the British Government; and of several other charges of "base and treacherous practises, discovered by the Bishop of Rochester, that the like had scarce been heard of, and seem'd to be what no man, endued with common sense, or the least drop of noble blood, could perpetrate; and that the King's friends were at a loss in not knowing what credit to give to such reports, tho' they apprehended the worst, from the directions he had lately given of having no correspondence with Mar or his adherents, from whom he had withdrawn all confidence."
Shortly after this declaration the Chevalier declared Colonel Hay to be his Secretary, and created the favourite Earl of Inverness; between whom and the Earl of Mar an antipathy, which had now become open hostility, prevailed. "The Duke of Mar," wrote the Earl of Inverness to Lockhart, "has declared himself my mortal enemy, only because I spoke truth to him, and could not, in my conscience, enter into his measures nor approve his conduct, tho' I always shunned saying any thing to his disadvantage, but to the King alone, from whom I thought I was obliged to conceal nothing."[169]
With respect to the treachery towards Atterbury, the justification of Lord Mar rests upon the testimony of Colonel Dillon, and other persons who saw the Earl's letter to Carteret. It is also certain that James accorded his approval to Mar's conduct in that affair. No positive intention of mischief can be made out against Mar; but his habit of rarely acting a straightforward part, his insatiable love of interference, and his mistaking cunning for policy, brought upon him the mournful indignation of the exiled Atterbury, and fixed upon him a grave imputation which it were almost impossible to wipe away.
Another charge brought by Atterbury against Lord Mar, was his advising James to barter his pretensions to the Crown for a pension. But this accusation is refuted by the two letters, of which vouchers are given in the Lockhart Papers, on which the allegation is founded. These letters were written from Geneva to the Prince and to Colonel Dillon.[170]
Lastly, Lord Mar stood charged with a scheme, discovered to Atterbury by Lord Inverness, for the restoration of the Stuarts, which, under pretence of replacing them on the throne, would for ever have rendered that restoration impracticable. From this allegation Lord Mar justified himself by referring to the scheme itself, which he was declared to have laid before the Regent of France with the intent to ruin James. Of this scheme, the two main features were, first to re-establish the ancient independence of Scotland and Ireland: secondly, that a certain number of French troops should remain in England, and that five thousand Scots, and as many Irish troops, should be sent to France and kept in pay by the French King, for a certain number of years. There is certainly a great deal of Mar's double policy, his being all things to all men, in such a scheme. He declared, however, and proved that he acquainted James with his plan in confidence, and that Colonel Hay sent a copy of it to the Bishop of Rochester. Little as one can approve of Mar's conduct, it is manifest that, by a deeply-laid intrigue, it was resolved for ever to uproot him from the confidence of James.
But the public career of Lord Mar had now drawn to its ignoble close. That he had his partisans, who repelled the charges against him by counter allegations, Lord Inverness soon found; and he began to think that "the less noise that was made about Mar," the better.[171]
During the year 1725, James further evinced his distrust of Lord Mar, by dismissing Mr. Sheldon, his supposed spy, and placing Mr. James Murray, a Protestant, as preceptor to the young Prince.
The retirement of the Princess Clementina into a convent, followed this last step. The correspondence of the royal couple, their recriminations, furnished, for some months, conversation for the continental courts, and even for St. James's, until the dismissal of Colonel Hay and his wife appeased the resolute daughter of the Sobieski, and produced an apparent reconciliation.
From the close of this altercation, and after the disgrace of Colonel Hay, the name of Lord Mar occurs no more in the history of the period. He resided at Paris until 1729, when, falling into ill health, he repaired to Aix la Chapelle, where he died in May 1732.