The intruder had disappeared by this time and I had got up and was peering out of the window as she came breathlessly into the living-room.
"What's the matter, Walter?" she asked.
"Some one broke into the house after those plans," I replied. "He escaped, but I got his picture, I think, by this device of Kennedy's. Let's go into a dark room and develop it."
There was no use trying to follow the man further. To Elaine's inquiry of what I meant, I replied by merely going over to the spot where I had hidden the camera and disconnecting it.
We went up-stairs where I had rigged up an impromptu dark room for my amateur photographic work some days before. Elaine watched me closely. At last I found that I had developed something. As I drew the film through the hypo tray and picked it up, I held it to the red light.
Elaine leaned over and looked at the film with me. There was a picture of a masked man, his cap down, in a startled attitude, his hands clapped to his face, completely hiding what the mask and cap did not hide.
"Well, I'll be blowed!" I cried in chagrin at the outcome of what I thought had been my cleverest coup.
A little exclamation of astonishment escaped Elaine. I turned to her.
"What is it?" I asked.
"The ring!" she cried.
I looked again more closely. On the little finger of the left hand was a peculiar ring. Once seen, I think it was not readily forgotten. "The ring!" she repeated excitedly. "Don't you remember—that ring? I saw it on Mr. Del Mar's hand—at his house—this afternoon!"