"And why?"
"Quite so. Why? When we answer that, we have made some progress with our little problem. Why? There can be only one adequate reason. Someone wanted to learn to imitate your writing, and had to procure a specimen of it first. And now if we pass on to the second point, we find that each throws light upon the other. That point is the request made by Pinner that you should not resign your place, but should leave the manager of this important business in the full expectation that a Mr. Hall Pycroft, whom he had never seen, was about to enter the office upon the Monday morning."
"My God!" cried our client, "what a blind beetle I have been!"
"Now you see the point about the handwriting. Suppose that someone turned up in your place who wrote a completely different hand from that in which you had applied for the vacancy, of course the game would have been up. But in the interval the rogue learnt to imitate you, and his position was therefore secure, as I presume that nobody in the office had ever set eyes upon you?"
"Not a soul," groaned Hall Pycroft.
"Very good. Of course, it was of the utmost importance to prevent you from thinking better of it, and also to keep you from coming into contact with anyone who might tell you that your double was at work in Mawson's office. Therefore they gave you a handsome advance on your salary, and ran you off to the Midlands, where they gave you enough work to do to prevent your going to London, where you might have burst their little game up. That is all plain enough."
"But why should this man pretend to be his own brother?"
"Well, that is pretty clear also. There are evidently only two of them in it. The other is personating you at the office. This one acted as your engager, and then found that he could not find you an employer without admitting a third person into his plot. That he was most unwilling to do. He changed his appearance as far as he could, and trusted that the likeness, which you could not fail to observe, would be put down to a family resemblance. But for the happy chance of the gold stuffing your suspicions would probably have never been aroused."
Hall Pycroft shook his clenched hands in the air. "Good Lord!" he cried. "While I have been fooled in this way, what has this other Hall Pycroft been doing at Mawson's? What should we do, Mr. Holmes? Tell me what to do!"
"We must wire to Mawson's."