"Again did Mrs. Middlemore decline to commit herself; again did she answer, 'It might, and it mightn't, sir.'
"'I presume there was nothing in the desk that attracted your attention besides the papers?'
"'Only one thing, sir--a curious sort of knife.'
"'A paper knife, most likely.'
"'It was more like a dagger,' said Mrs. Middlemore. 'It 'ad a 'andle like a twisted snake, with a' open mouth and a colored stone in its eye. It 'ad a sharp pint, too?'
"'How did you become aware of that? Did you ever try it?'
"'Not me, sir; but once I come in when Mr. Felix 'ad it in 'is 'and, playing with it, and all at once he dropped it like a 'ot pertater. He pricked 'isself with it, and there was blood on 'is 'and.'
"'You have furnished me with a valuable piece of evidence, Mrs. Middlemore. Papers are easily burnt, and a desk broken up and destroyed. It would not be so easy to get rid of that knife, which, from your description, must be a foreign dagger, and the identification of which would be a simple matter. For instance, you could swear to it, and so could I, who have never seen it.'
"'Anybody could swear to it, sir; it couldn't be mistook.'
"'Did M. Felix keep this dagger always in his desk?'