But that sister was _not_ dead. And herein follow the facts that have come to light of the means her husband employed to make her seem so, and of his motives for employing them.
To see these clearly you must keep in mind that Thornton was tied for life within the limits of the penal settlements. Maisie was free to go; with her it was merely a question of money. As time went on, her yearning to see her child and her twin-sister again grew and grew, and her appeals to her husband to allow her sometime to revisit England in accordance with his promise became every year more and more urgent. He would be quite a rich man soon--why should she not? Well--simply that she might not come back! That was his view, and we have to bear in mind that it would have been impossible for him to replace her, except from among female convicts assigned to settlers; nominally as servants, but actually as mates on hire--suppose we call them. One need not say much of this unhappy class; it is only mentioned to show that Thornton could have found no woman to take the place of the beautiful and devoted helpmeet whose constancy to him had survived every trial. No wonder he was ill at ease with the idea of her adventuring back to England alone. But it took a mind as wicked as his to conceive and execute the means by which he prevented it. It seems to have been suggested by the fact that the distribution of letters in his district had been assigned to him by the Governor. This made it easy to deliver them or keep them back, when it was in his interest to do so, without fear of detection. The letters coming from England were few indeed, so he was able to examine them at leisure.
At first he was content to withhold Phoebe's letters, hoping that Maisie would be satisfied with negative evidence of her death, which he himself suggested as the probable cause of their suspension. But when this only increased her anxiety to return to her native land, he cast about for something he could present as direct proof. The death of her father supplied the opportunity. A black-edged sheet came, thickly written with Phoebe's account of his last illness, in ink which, as the event showed, did not defy obliteration. Probably Thornton had learned, among malefactors convicted of his own offence, secrets of forgery that would seem incredible to you or me. He contrived to obliterate this sheet all but the date-stamps outside, and then--the more readily that he had been informed that only fraud for gain made forgery felony--elaborated as a palimpsest a most careful letter in the handwriting of the father announcing Phoebe's own death, and also that of the daughter whom Maisie had bequeathed to her care. He must have been inspired and upborne in this difficult task by the spirit of a true artist. No doubt all _faussure_, to any person with an accommodating moral sense, is an unmixed delight. This letter remains, and has been seen by the present writer and others. The dexterity of the thing almost passes belief, only a few scarcely perceptible traces of the old writing being visible, the length of the new words being so chosen as to hide most of the old ones. What is even more incredible is that the original letter from Phoebe was deciphered at the British Museum by the courtesy of the gentlemen engaged in the deciphering and explanation of obscure inscriptions.