“Now the policeman Green had served several years at the station of Wilcannia as a mounted trooper. He was an experienced bushman. The day he left Sydney is known. It was the second day of his annual leave, and it was the day after he had drawn the sum of thirteen hundred and seven pounds from his bank. A week before that he had sold house property to the tune of several thousands. Knowing the crash was imminent, he realized all his assets and cleared off with the cash, and doubtless securities as well.

“You see, Sergeant, we now have a horse of a different colour. It is unlikely that Marks, or Green, would have become bushed, even though drunk. Again, we may almost be sure that he had a lot of money and negotiable securities with him. Here we have a motive for murder. Even without your photograph of the abandoned car the case would be attractive enough to me. The photograph, however, is the crowning point, the basis of my conviction that Marks was murdered, not by the bush, but by some white man.”

“And you arrive at that theory from my photo of the car?” exclaimed Morris in amazement.

“Precisely,” Bony said slowly. “When you photographed the car you also photographed evidence of murder which to me is almost irrefutable.”

With obvious delight Bony watched the effect of his bomb. No less than his illustrious prototype did he revel in dramatic situations and startling denouements. His expression then was one of amused satisfaction. He went on:

“This is a case, Sergeant, worthy of my attention. I start my inquiries two months after the crime was committed. Nature has obliterated all tracks, and has had ample time to bury all clues deeply in sand. There is no corpse as a fingerpost to the murderer, as there is in nine hundred and ninety-nine cases in a thousand. Even if I find a corpse, the ants and crows will likely enough have picked the bones nice and clean. There will be no fingerprints; no autopsy is possible; and, because of all this, poor old Bony is going to have a really enjoyable time.”