The assurance seemed unnecessary, but I did not regret giving it when I saw how it relieved him of all doubt, and caused his eye to lighten and his manner to grow easy as he went on to say:
"So far as mortal calculation can go, this room has not been entered by anyone but the police or persons acting under the instructions of the police, since the hour when Mr. Gillespie was carried out of it. Consequently we have a right to expect all articles remaining here to be in the same condition as on that night. This, for instance."
He had taken out the typewriter from a closet built in one of the corners, and set it as he spoke down in its old place on the edge of the desk.
"Ah!" I burst forth. "Your idea is in connection with this typewriter!"
He frowned, or almost frowned, for he was an amiable fellow; then, giving me a pleading look, observed:
"I am young yet, Mr. Outhwaite, and it is very easy for me to deceive myself with imaginary results. You will therefore allow me a minute to myself, and if I find out that I have struck a false trail, or if my idea proves to be one I cannot sustain by facts, I'll sing out and we will consult as to our next move."
"Shall I step outside?" I asked.
But this he would not listen to.
"All I want," said he, "is for you to look the other way while I stoop over this typewriter."
I naturally felt disposed to humour him, and meanwhile he remained so still that I was confident he did not touch the instrument. But the cry which impetuously burst from him after a moment of intense stillness startled me so I can never forget it. It was something between a sob and a shout, and it was so suggestive of triumph that I could not forbear turning about and rushing up to the instrument over which he still stooped.