The earliest known decided reference to the Letters is that of the Spanish Ambassador, de Silva, writing from London on July 12, 1567. He says that du Croc, the French Ambassador to Mary, has passed through town on his return from Scotland. The French Ambassador in London, La Forest, reports to de Silva that Mary’s ‘adversaries assert positively that they know she had been concerned in the murder of her husband, which was proved by letters under her own hand, copies of which were in his [whose?] possession.’[214] Major Martin Hume writes, in his Preface to the Calendar, ‘The many arguments against their genuineness, founded upon the long delay in their production, thus disappear.’ It does not necessarily follow, however, that the letters of which du Croc probably carried copies (unless La Forest merely bragged falsely, to vex his Spanish fellow diplomatist) were either wholly genuine, or were identical with the letters later produced. It is by no means certain that Lethington and Sir James Balfour had not access, before June 21, to the Casket, which was in Balfour’s keeping, within Edinburgh Castle. Randolph later wrote (as we have already seen) that the pair had opened a little ‘coffer,’ with a green cloth cover, and taken out the band (which the pair had signed) for Darnley’s murder.[215] Whether the Casket was thus early tampered with is uncertain. But, as to du Croc’s copies of the Letters, the strong point, for the accusers, is, that, when the Letters were published, in Scots, Latin, and French, four years later, we do not hear that any holders of du Croc’s copies made any stir, or alleged that the copies did not tally with those now printed, in 1571-1573, by Mary’s enemies. This point must be kept steadily in mind, as it is perhaps the chief objection to the theory which we are about to offer. But, on November 29, 1568, when Mary’s accusers were gathered in London to attack her at the Westminster Conference, La Forest’s successor, La Mothe Fénelon, writes to Charles IX. that they pretend to possess incriminating letters ‘_escriptes et signées de sa main_;’ written and _signed_ by her hand. Our _copies_ are certainly not signed, which, in itself, proves little or nothing, but Mary’s contemporary defenders, Lesley and Blackwood, urge that there was not even a pretence that the Letters were signed, and this plea of theirs was not answered. My point, however, is that though La Forest, according to de Silva, had copies in July 1567, his successor at the English Court, doubtless well instructed, knows nothing about them, as far as his despatch shows. But he does say that the accusers are in search of evidence to prove the Letters authentic, not forged.[216] He says (November 28) to Catherine de’ Medici, that he thinks the proofs of Mary’s accusers ‘very slender and extremely impertinent,’ and he has been consulted by Mary’s Commissioners.[217]