“Elementary,” said he. “It is one of those instances where the reasoner can produce an effect which seems remarkable to his neighbour, because the latter has missed the one little point which is the basis of the deduction. The same may be said, my dear fellow, for the effect of some of these little sketches of yours, which is entirely meretricious, depending as it does upon your retaining in your own hands some factors in the problem which are never imparted to the reader. Now, at present I am in the position of these same readers, for I hold in this hand several threads of one of the strangest cases which ever perplexed a man’s brain, and yet I lack the one or two which are needful to complete my theory. But I’ll have them, Watson, I’ll have them!” His eyes kindled and a slight flush sprang into his thin cheeks. For an instant only. When I glanced again his face had resumed that red-Indian composure which had made so many regard him as a machine rather than a man.
“The problem presents features of interest,” said he. “I may even say exceptional features of interest. I have already looked into the matter, and have come, as I think, within sight of my solution. If you could accompany me in that last step you might be of considerable service to me.”
“I should be delighted.”
“Could you go as far as Aldershot to-morrow?”
“I have no doubt Jackson would take my practice.”
“Very good. I want to start by the 11.10 from Waterloo.”
“That would give me time.”
“Then, if you are not too sleepy, I will give you a sketch of what has happened, and of what remains to be done.”
“I was sleepy before you came. I am quite wakeful now.”
“I will compress the story as far as may be done without omitting anything vital to the case. It is conceivable that you may even have read some account of the matter. It is the supposed murder of Colonel Barclay, of the Royal Mallows, at Aldershot, which I am investigating.”