I nodded.

“I think it has, Miss Holcomb.  And I can understand poor Chick.  He is a very brave man.  It’s a strange jewel and of terrible potency; that much I know.  It devitalises; it destroys.  I can feel it already.  It covers life with a fog of decay.  The same solitude has come upon myself.  Nevertheless I am certain it has much to do with the Blind Spot.  It is a key of some sort.  The very interest of the Rhamda and the Nervina tells us that.  I think it was through this stone that your father made his discovery.”

She thought a moment.

“Hadn’t you better return it?  While you still have health?  If you keep it, it will be only one more.”

“You forget, Miss Holcomb, my promise to Chick.  I loved your father, and I was fond of Watson.  It’s a great secret and, if the professor is right, one which man has sought through the ages.  I’d be a coward to forgo my duty.  If I fail, I have another to take my place.”

“Oh,” she said, “it’s horrible.  First father; then Chick; now you; and afterwards it will be Mr. Fenton.”

“It is our duty,” I returned.  “One by one.  Though we may fail, each one of us may pass a bit more on to his successor.  In the end we win.  It is the way of man.”

I had my way.  She turned over all the data and notes that had been left by the professor; but I never found a thing in them that could be construed to an advantage.  My real quest was to trace down the jewel.  The man Kennedy’s full name was, I learned, Budge Kennedy.  He had lived in Oakland.  It was late in the afternoon when I parted with Miss Holcomb and started for the city.

I remember it well because of a little incident that occurred immediately after our parting.  I was just going down the steps when I looked up one of the side streets.  A few students were loitering here and there.  But there was one who was not a student.  I recognised him instantly, and I wondered.  It was the Rhamda.  This was enough to make me suspicious.  But there was one thing more.  Farther up the street was another figure.

When I came down the steps the Rhamda moved, and his move was somehow duplicated by the other.  In itself this was enough to clear up some of my doubts concerning the phantom.  His actions were too simple for an apparition.  Only a man would act like that, and a crude one.  I didn’t know then the nerve of the Rhamda.  There was no doubt that I was being shadowed.

To make certain, I took the by-streets and meandered by a devious route to the station.  There was no question; one and two they followed.  I knew the Rhamda; but who was the other?

At the station we purchased tickets, and when the train pulled in I boarded a smoker.  The other two took another coach—­the stranger was a thick-set individual with a stubby, grey moustache.  On the boat I didn’t see them; but at the ferry building I made a test to see that I was followed.  I hailed a taxi and gave specific instructions to the driver.