"I thought you were convinced of Bella's guilt."
"I was."
"Well, then, you must know when your ideas changed."
Mrs. Bradley was silent for a minute or two. One would have said that she was in contemplation of the hedge which divided part of her garden from the paddock. "I don't know," she repeated, "but if I am being asked to hazard an opinion, I would say that I was convinced of Bella's guilt until I went to see her down in Devon."
Ferdinand nodded, as his mother turned her basilisk eyes on him.
"Personally," he said, "I did not think anything could disprove Bella Foxley's guilt. The ancient, wealthy aunt, the blackmailing cousin, the dangerous and criminally minded boys, and the golden opportunity of making herself safe for life by assuming the identity of a murdered sister—the thing seemed self-evident, fool-proof, satisfactory and horrible."
"But it wasn't altogether satisfactory," said Mrs. Bradley, "as I realized the moment I began to examine it from Bella Foxley's point of view. If you assume for a moment that Bella was not guilty, you get a different impression entirely of the course events may have taken. You get the impression, for instance, that every ill deed we had attributed to Bella could just as well have been performed by Muriel."
"That means, though, that the aunt died accidentally," said Ferdinand. "Bella was the only person to have had a motive there for murder."
"Not necessarily," replied his mother. "Bella certainly had the motive, for she stood to gain by the death, but if she could be blackmailed successfully, Tom and Muriel stood to gain something too. It was a clever plot, but it was apparent, before I suspected Muriel at all, that Tom was somewhere involved. It was evident that Bella had not written that diary."
"The diary?"
"Yes. You've read it. You know what the mistakes and discrepancies were. Some of the mistakes could, but others could not, have been made by a single author, especially if that author were Bella. Collaboration was indicated—an unheard-of thing in a genuine diary."
"I see what you mean. But there was no way of telling which part was Bella's own work, was there? And, even if there were, the only other part-author of the diary, as you say, could have been Tom. At least, let's put it that the collaborator couldn't have been Muriel."
"There was no need for it to have been Muriel. I spoke just now of a plot. But, to revert to the diary itself, it seemed to me to indicate that the writer had a rather pleasing style, and a definite, although possibly rudimentary, sense of form. Of course, we must admit that Bella may have possessed both these literary qualities, but Tom, as a practising writer (he made some of his income out of articles for journals devoted to psychical research, you will remember), was the more likely author, on the whole, in my opinion. Still, one cannot generalise about such things, for it is a well-known fact that people whose powers of conversation are crude, boorish, unready, or even, for all social purposes, non-existent, can sometimes contrive to express themselves, when in receipt of pen and paper, in unexceptionable prose."
"I don't see, all the same, why you think two people wrote the diary between them," said Caroline.
"I don't know that they did. Bella was an unconscious collaborator. What interested me, and caused me to investigate the matter in the first place, were the ending of the diary, abrupt yet undramatic, and the mistakes in fact which were apparent almost at a glance and which became ludicrously obvious as soon as one began to examine the matter.
"Then came the very odd fact that, although the diary continued long past the time when everyone concerned had left Aunt Flora's house, the diary itself remained there. That seemed very curious."
"Last entries faked? Written beforehand ?" said Ferdinand.
"It added to my idea that there was a plot. The plot, of course, came into being when Bella helped Pegwell and Kettle-borough to escape from the Institution. Well, the arrangement between Bella and Tom was that the boys should remain hidden in the haunted house, where Tom could make good use of them in faking the poltergeist phenomena, and where, Bella hoped, they would be safe from the police.
"That, I fancy, was as far as Tom was prepared to go, and, apart from Muriel's confession, I could not prove much of what follows.
"One thìng which Tom never allowed for, of course, was the horrid jealousy which his necessary collusion with Bella over the boys evoked in Muriel. This jealousy led Muriel, later on, to kill him and to see that Bella was charged with the murder."
"Didn't Bella know who had killed Tom?" Caroline enquired.
"She thought it was the boys. She does not seem to have suspected Muriel of that until now."
"Then did Muriel kill the aunt?"
"It is most likely. But it doesn't matter now, in one sense, whether she did or not. The death of the aunt suggested to Tom this further plot to continue to blackmail Bella—not that he did anything so crude, I imagine, as to extort money by threats, or anything of that kind. Bella loved him, and he found it easy enough to get the money. It was, of course, very much more than those small amounts suggested at the trial. It was, very possibly, the half which was supposed to have gone to Tessa, although Bella did not admit it."
"Well, he wrote the diary, intending to type it out later and threaten Bella with it if ever it became necessary to apply a little pressure. He purposely sent it to the house to Eliza Hodge, being pretty sure that the old servant would take care of it without being unduly curious about it. Then he wrote the anonymous letters and drove Bella almost mad, I should imagine, by the accusations of murder contained in them. Then he fell out of the window that first time, and allowed her to believe that the boys had pushed him out."
"And that gave Muriel the idea of how to kill him without being suspected?" asked Caroline.
"Yes. She has now confessed it. I had an inkling of what had happened—I think we all had—when we heard about the button which was found in the dead man's hand."
"Well, it was rather silly of Bella to go and visit Tom so late at night," said Caroline. Mrs. Bradley looked benevolently at her daughter-in-law, and agreed.
"There is one thing I don't understand," said Ferdinand. "How did a comparatively frail woman such as Muriel contrive to get the two boys battened down under hatches in that cellar? I should have thought the lads would have popped up the well whilst she was screwing down the trap-door, or vice-versa."
"Oh, Bella helped her over that."
"So Bella is partly guilty?"
"No, but it flummoxed her at the trial. Tom must have told her that the boys had pushed him out and were dangerous. She suggested that they should shut the boys up until they had decided what was the best thing to do about them. She knew, of course, that, following the information which she was going to give at the inquest, it was almost certain that Bella would be arrested for murdering Tom. After that, Muriel dared not keep the boys alive in case they could witness against her. The probability was that they had been fast asleep at the time, but her guilty conscience would not allow her to run any risks.
"When Bella had been acquitted of the murder of Tom, she knew, from the way in which Muriel had given her evidence, that she had an implacable enemy, and she knew the reason for it. It was to escape from Muriel's hatred, I think, that she assumed Tessa's identity, although I am certain that she never suspected that Muriel had killed Tom. She did think, though, that Muriel had choked Aunt Flora.