“In short, the whole of this peculiar set of curcumstances—­the change in Jeffrey’s habits, the change in his signature, and the execution of his strange will—­came into existence about the time when Mrs. Wilson was first known to be suffering from cancer.

“This struck me as a very suggestive fact.

“Then there is the extraordinarily opportune date of Mr. Jeffrey’s death.  Mrs. Wilson died on the twelfth of March.  Mr. Jeffrey was found dead on the fifteenth of March, having apparently died on the fourteenth, on which day he was seen alive.  If he had died only three days sooner, he would have predeceased Mrs. Wilson, and her property would never have devolved on him at all; while, if he had lived only a day or two longer, he would have learned of her death and would certainly have made a new will or codicil in his nephew’s favour.

“Circumstances, therefore, conspired in the most singular manner in favour of John Blackmore.

“But there is yet another coincidence.  Jeffrey’s body was found, by the merest chance, the day after his death.  But it might have remained undiscovered for weeks, or even months; and if it had, it would have been impossible to fix the date of his death.  Then Mrs. Wilson’s next of kin would certainly have contested John Blackmore’s claim—­and probably with success—­on the ground that Jeffrey died before Mrs. Wilson.  But all this uncertainty is provided for by the circumstance that Mr. Jeffrey paid his rent personally—­and prematurely—­to the porter on the fourteenth of March, thus establishing beyond question the fact that he was alive on that date; and yet further, in case the porter’s memory should be untrustworthy or his statement doubted, Jeffrey furnished a signed and dated document—­the cheque—­which could be produced in a court to furnish incontestable proof of survival.

“To sum up this part of the evidence.  Here was a will which enabled John Blackmore to inherit the fortune of a man who, almost certainly, had no intention of bequeathing it to him.  The wording of that will seemed to be adjusted to the peculiarities of Mrs. Wilson’s disease; and the death of the testator occurred under a peculiar set of circumstances which seemed to be exactly adjusted to the wording of the will.  Or, to put it in another way:  the wording of the will and the time, the manner and the circumstances of the testator’s death, all seemed to be precisely adjusted to the fact that the approximate date of Mrs. Wilson’s death was known some months before it occurred.

“Now you must admit that this compound group of coincidences, all conspiring to a single end—­the enrichment of John Blackmore—­has a very singular appearance.  Coincidences are common enough in real life; but we cannot accept too many at a time.  My feeling was that there were too many in this case and that I could not accept them without searching inquiry.”

Thorndyke paused, and Mr. Marchmont, who had listened with close attention, nodded, as he glanced at his silent partner.