“‘Have you seen anybody go this way?’ he asked.  ’A young man, running hard?  A young man in knickerbockers?’

“‘N—­no,’ I answered, trembling; for I was afraid to confess.  ’Not a soul has gone past!’

“Of course, I didn’t know of the murder as yet; and I only wanted to get off unperceived to the station.

“I’d bound up my hand in my handkerchief by that time, and held it tight under my cloak.  I went back by train unnoticed, and returned to my friends’ house.  I hadn’t even told them I was going to Woodbury at all.  I pretended I’d been spending the day at Whittingham.  Next morning, I read in the paper of your father’s murder.”

I stared hard at Aunt Emma.

“Why didn’t you tell me this long ago?” I cried, in an agony of suspense.  “Why didn’t you give evidence and say so at the inquest?”

“How could I?” Aunt Emma answered, looking back at me appealingly.  “The circumstances were too suspicious.  As it was, everybody was running after the young man in knickerbockers.  Nobody took any notice of a little old lady in a long grey dust-cloak.  But if once I’d confessed and shown my wounded hand, who would ever have believed I’d nothing to do with the murder?—­except you, perhaps, Una.  Oh no:  I came back here to my own home as fast as ever I could; for I was really ill.  I took to my bed at once.  And as nobody called me to give evidence at the inquest, I said nothing to anybody.”

“But the bicycle!” I cried.  “The bicycle!  You ought to have mentioned that.  You were the only one who saw it.  It was a clue to the murderer.”

“If I’d told,” Aunt Emma answered, “I should never have been allowed to take charge of you at all.  I thought my one clear duty was to my sister’s child:  it was to take care of your health in your shattered condition.  And even now, Una, I tell you only for this:  if you find out anything new, in Canada or here, try not to drag me into it.  I couldn’t stand the strain.  Cross-examination would kill me.”

“I’ll remember it, auntie,” I said, wearied out with excitement.  “But I think you did wrong, all the same.  In a case like this, it’s everybody’s first duty to tell all he knows, in the interests of justice.”

However, this confession of Aunt Emma’s rendered one thing more certain to me than ever before.  I was sure I was on the right track now, after Courtenay Ivor.  The bicycle clinched the proof.

But I said nothing as yet to the police, or to my friendly Inspector.  I was determined to hunt the whole thing up on my own account first, and then deliver my criminal, when fully secured, to the laws of my country.

Not that I was vindictive.  Not that I wanted to punish the man.  No; I shrank terribly from the task.  But to relieve myself from this persistent sense of surrounding mystery, and to free others from suspicion, I felt compelled to discover him.  It seemed to me like a duty laid upon me from without.  I dared not shirk it.