He found the ladder after a short search and stood at the bottom, looking up at me.  “Well, I suppose you haven’t seen him?” he inquired.  “There are enough darned cubbyholes in this house to hide a patrol wagon load of thieves.”  He lighted a fresh match.  “Hello, here’s another door!”

By the sound of his diminishing footsteps I supposed it was a rear staircase.  He came up again in ten minutes or so, this time with the policeman.

“He’s gone, all right,” he said ruefully.  “If you’d been attending to your business, Robison, you’d have watched the back door.”

“I’m not twins.”  Robison was surly.

“Well,” I broke in, as cheerfully as I could, “if you are through with this jolly little affair, and can get down my ladder without having my housekeeper ring the burglar alarm, I have some good Monongahela whisky—­eh?”

They came without a second invitation across the roof, and with them safely away from the house I breathed more freely.  Down in the den I fulfilled my promise, which Johnson drank to the toast, “Coming through the rye.”  He examined my gun rack with the eye of a connoisseur, and even when he was about to go he cast a loving eye back at the weapons.

“Ever been in the army?” he inquired.

“No,” I said with a bitterness that he noticed but failed to comprehend.  “I’m a chocolate cream soldier—­you don’t read Shaw, I suppose, Johnson?”

“Never heard of him,” the detective said indifferently.  “Well, good night, Mr. Blakeley.  Much obliged.”  At the door he hesitated and coughed.

“I suppose you understand, Mr. Blakeley,” he said awkwardly, “that this—­er—­surveillance is all in the day’s work.  I don’t like it, but it’s duty.  Every man to his duty, sir.”

“Sometime when you are in an open mood, Johnson,” I returned, “you can explain why I am being watched at all.”

CHAPTER XV

THE CINEMATOGRAPH

On Monday I went out for the first time.  I did not go to the office.  I wanted to walk.  I thought fresh air and exercise would drive away the blue devils that had me by the throat.  McKnight insisted on a long day in his car, but I refused.

“I don’t know why not,” he said sulkily.  “I can’t walk.  I haven’t walked two consecutive blocks in three years.  Automobiles have made legs mere ornaments—­and some not even that.  We could have Johnson out there chasing us over the country at five dollars an hour!”

“He can chase us just as well at five miles an hour,” I said.  “But what gets me, McKnight, is why I am under surveillance at all.  How do the police know I was accused of that thing?”

“The young lady who sent the flowers—­she isn’t likely to talk, is she?”

“No.  That is, I didn’t say it was a lady.”  I groaned as I tried to get my splinted arm into a coat.  “Anyhow, she didn’t tell,” I finished with conviction, and McKnight laughed.