‘I will recapitulate the vital points in a brief summary: The will was signed by Mr Clode, placed by me in an envelope—so far so good. It was then put by me in my overcoat pocket. That overcoat was taken from me by Mary and handed by her to George, who was in full sight of me whilst handling the coat. During the time that I was in the study Mrs Eurydice Spragg would have had plenty of time to extract the envelope from the coat pocket and read its contents and, as a matter of fact, finding the envelope on the ground and not in the pocket seemed to point to her having done so. But here we come to a curious point: she had the opportunity of substituting the blank paper, but no motive. The will was in her favour, and by substituting a blank piece of paper she despoiled herself of the heritage she had been so anxious to gain. The same applied to Mr Spragg. He, too, had the opportunity. He was left alone with the document in question for some two or three minutes in my office. But again, it was not to his advantage to do so. So we are faced with this curious problem: the two people who had the opportunity of substituting a blank piece of paper had no motive for doing so, and the two people who had a motive had no opportunity. By the way, I would not exclude the housemaid, Emma Gaunt, from suspicion. She was devoted to her young master and mistress and detested the Spraggs. She would, I feel sure, have been quite equal to attempting the substitution if she had thought of it. But although she actually handled the envelope when she picked it up from the floor and handed it to me, she certainly had no opportunity of tampering with its contents and she could not have substituted another envelope by some sleight of hand (of which anyway she would not be capable) because the envelope in question was brought into the house by me and no one there would be likely to have a duplicate.’

He looked round, beaming on the assembly.

‘Now, there is my little problem. I have, I hope, stated it clearly. I should be interested to hear your views.’

To everyone’s astonishment Miss Marple gave vent to a long and prolonged chuckle. Something seemed to be amusing her immensely.

‘What is the matter, Aunt Jane? Can’t we share the joke?’ said Raymond.

‘I was thinking of little Tommy Symonds, a naughty little boy, I am afraid, but sometimes very amusing. One of those children with innocent childlike faces who are always up to some mischief or other. I was thinking how last week in Sunday School he said, “Teacher, do you say yolk of eggs is white or yolk of eggs are white?” And Miss Durston explained that anyone would say “yolks of eggs are white, or yolk of egg is white”—and naughty Tommy said: “Well, I should say yolk of egg is yellow!” Very naughty of him, of course, and as old as the hills. I knew that one as a child.’