The charges against him, as all readers of Scotch literature know well, may be reduced to two heads. 1st. The letters and sonnets were forgeries. Maitland of Lethington may have forged the letters; Buchanan, according to some, the sonnets. Whoever forged them, Buchanan made use of them in his Detection, knowing them to be forged. 2nd. Whether Mary was innocent or not, Buchanan acted a base and ungrateful part in putting himself in the forefront amongst her accusers. He had been her tutor, her pensioner. She had heaped him with favours; and, after all, she was his queen, and a defenceless woman: and yet he returned her kindness, in the hour of her fall, by invectives fit only for a rancorous and reckless advocate, determined to force a verdict by the basest arts of oratory.
Now as to the “casket” letters. I should have thought they bore in themselves the best evidence of being genuine. I can add nothing to the arguments of Mr. Froude and Mr. Burton, save this: that no one clever enough to be a forger, would have put together documents so incoherent, and so incomplete. For the evidence of guilt which they contain is, after all, slight and indirect, and, moreover, superfluous altogether; seeing that Mary’s guilt was open and palpable, before the supposed discovery of the letters, to every person at home and abroad who had any knowledge of the facts. As for the alleged inconsistency of the letters with proven facts: the answer is, that whosoever wrote the letters would be more likely to know facts which were taking place around them than any critic could be one hundred or three hundred years afterwards. But if these mistakes as to facts actually exist in them, they are only a fresh argument for their authenticity. Mary, writing in agony and confusion, might easily make a mistake: forgers would only take too good care to make none.