‘Who put it there?’

’That is precisely what I wish you to find out,—­what I wish you to make it your instant business to ascertain.  I have found the thing, under similar circumstances, on three separate occasions, on my study table,—­and each time it has had on me the same hideous effect.’

’Each time after you have returned from a late sitting in the House of Commons?’

‘Exactly.’

‘Where are these—­what shall I call them—­delineations?’

‘That, again, I cannot tell you.’

‘What do you mean?’

‘What I say.  Each time, when I recovered, the thing had vanished.’

‘Sheet of paper and all?’

’Apparently,—­though on that point I could not be positive.  You will understand that my study table is apt to be littered with sheets of paper, and I could not absolutely determine that the thing had not stared at me from one of those.  The delineation itself, to use your word, certainly had vanished.’

I began to suspect that this was a case rather for a doctor than for a man of my profession.  And hinted as much.

’Don’t you think it is possible, Mr Lessingham, that you have been overworking yourself—­that you have been driving your brain too hard, and that you have been the victim of an optical delusion?’

’I thought so myself; I may say that I almost hoped so.  But wait till I have finished.  You will find that there is no loophole in that direction.’

He appeared to be recalling events in their due order.  His manner was studiously cold,—­as if he were endeavouring, despite the strangeness of his story, to impress me with the literal accuracy of each syllable he uttered.

’The night before last, on returning home, I found in my study a stranger.’

‘A stranger?’

‘Yes.—­In other words, a burglar.’

‘A burglar?—­I see.—­Go on.’

He had paused.  His demeanour was becoming odder and odder.

’On my entry he was engaged in forcing an entry into my bureau.  I need hardly say that I advanced to seize him.  But—­I could not.’

‘You could not?—­How do you mean you could not?’

’I mean simply what I say.  You must understand that this was no ordinary felon.  Of what nationality he was I cannot tell you.  He only uttered two words, and they were certainly in English, but apart from that he was dumb.  He wore no covering on his head or feet.  Indeed, his only garment was a long dark flowing cloak which, as it fluttered about him, revealed that his limbs were bare.’

‘An unique costume for a burglar.’

’The instant I saw him I realised that he was in some way connected with that adventure in the Rue de Rabagas.  What he said and did, proved it to the hilt.’

‘What did he say and do?’

’As I approached to effect his capture, he pronounced aloud two words which recalled that awful scene the recollection of which always lingers in my brain, and of which I never dare to permit myself to think.  Their very utterance threw me into a sort of convulsion.’