So much for the “motive,” which presents little difficulty.  Then, with regard to the question whether, on the assumption of his guilt, Mary Blandy was the intelligent agent of Cranstoun or his innocent dupe, no one who has studied the evidence against her can entertain a reasonable doubt.  Apart from the threatening and abusive language which she applied to her father, her whole attitude towards his last illness shows how false were her subsequent professions of affection.  She herself has disposed of the suggestion that she really believed in the love-compelling properties of the magic powder, though such a belief was not inconceivable, as appears from the contemporary advertisement of a “Love Philtre,” of which a copy is printed in the Appendix.  She told her dying father that if he were injured by the powder, she was not to blame, as “it was given her with another intent.”  What that “intent” was she did not then explain, but later she informed Dr. Addington that it was to “make him [her father] kind” to Cranstoun and herself.  In the speech which she delivered in her own defence she said, “I gave it to procure his love”; and again, on the conclusion of Bathurst’s reply, “It is said I gave it my father to make him fond of me:  there was no occasion for that—­but to make him fond of Cranstoun.”  In her Narrative she repeats this statement; but in her Own Account, written and revised by herself, she says, “I gave it to my poor father innocent of the effects it afterwards produced, God knows; not so stupid as to believe it would have that desired, to make him kind to us; but in obedience to Mr. Cranstoun, who ever seemed superstitious to the last degree.”  Here we have an entirely fresh (if no less false) reason assigned for the exhibition of the wise woman’s drug; only, of course, another lie, but one which, disposes of her previous defence.  Of the true qualities of the powder she had ample proof; she warned the maid that the gruel “might do for her,” she saw its virulent effects upon Gunnell and Emmet, as well as on her father from its first administration, while her concealment of its use from the physician, and her destruction of the remanent portion, are equally incompatible with belief either in its innocence or her own.  Finally, her burning of Cranstoun’s letters, which, if her story was true, were her only means of confirming it, her attempts to bribe the servants, and her statements to Fisher and the Lanes at the Angel, afford, in Mr. Baron Legge’s phrase, “a violent presumption” of her guilt.

Cranstoun, even at the time, did not lack apologists, who held that Miss Blandy, herself the solo criminal, cunningly sought to involve her guileless lover in order to lessen her own guilt.  This view has been endorsed by later authorities.  Anderson, in his Scottish Nation, remarks, “There does not appear to have been any grounds for supposing that the captain was in any way accessory to the murder”; and Mr. T.F.  Henderson, in his article on Cranstoun