“Well,” he said, as Thorndyke returned to his chair with the letter in his hand, “has the oracle spoken? Have we made any startling discoveries?”
“I wouldn’t use the word ‘discoveries,’ ” replied Thorndyke, “which seems to imply facts definitely ascertained; but there are certain appearances which suggest a rather startling inference.”
“Indeed!” said Mr. Penfield, taking snuff with great enjoyment. “I somehow expected that they would when I decided to show you the letter. What is the inference that is suggested?”
“The inference is,” replied Thorndyke, “that this letter has never been through the post.”
Mr. Penfield paused with his hand uplifted, holding a minute pinch of snuff, and regarded Thorndyke in silent astonishment.
“That,” he said, at length, “is certainly a startling inference; and it would be still more startling if there were any possibility that it could be true. Unfortunately the letter bears a post-mark showing that it was posted at Woodbridge, and another showing that it was sorted at the London office. But no doubt you have observed and allowed for those facts.”
“The appearances,” said Thorndyke, “suggest that when the post-marks were made, the envelope was empty and probably unaddressed.”
“But, my dear sir,” protested Penfield, “that is a manifest impossibility. You must see that for yourself. How could such a thing possibly have happened?”
“That is a separate question,” replied Thorndyke. “I am now dealing only with the appearances. Let me point them out to you. First, you will notice that the words ‘Personal and Confidential’ have been written at the top of the envelope. Apparently the word ‘Personal’ was first written alone and the words ‘and Confidential’ added as an afterthought. That is suggested by the change in the writing and the increasingly condensed form of the letters towards the end due to the want of space. But in spite of the squeezing up of the letters, the tail of the final l has been forced onto the stamp and actually touches the circle of the post-mark; and if you examine it through this lens, you can see plainly that the written line is on top of the post-mark. Therefore the post-mark was already there when that word was written.”
He handed the envelope and the lens to Mr. Penfield, who, after some ineffectual struggles, rejected the lens and had recourse to his spectacles.