letter I had received from London, copying the remainder of the

postmark with a little lampblack. Then I went down to Grenelle in the middle of Monday night and dropped the letter into Dupierre’s box. He would find it next morning all correct with its English stamp, cancelled in a London office.’

In spite of their loathing for this callous and cynical criminal, La Touche and Mallet could not but be impressed by the cleverness of the trick. All the detectives concerned had argued that as the order for the statue had been received apparently from London on Tuesday, it must have been posted there on Monday, and that as Felix was there and Boirac in Paris, the former must have posted it. But how simply they had been duped! Truly, thought the detectives with unwilling admiration, Boirac had deserved to succeed.

‘But the tracing?’ persisted La Touche.

‘I thought that not only must Dupierre believe the letter came from London, but some definite proof that Felix had written it must be provided. I did it in this way. After I had written the letter I made a careful tracing of it on a bit of tracing paper. As you probably know, I visited St. Malo when in London, and there, with Felix’s pen and ink, I retraced over the writing and blotted it. This gave the impression.’

Again his hearers had to admit a rueful admiration for the ingenious ruse. The finding of the impression had seemed so conclusive, and--it was only a trick. And what a simple trick--when you knew it!

‘That is quite clear, thank you,’ said La Touche.

‘I met the cask in London and brought it to the shed,’ went on the manufacturer. ‘There, after dismissing the carter, I opened the cask, took out the statue, packed it in a portmanteau I had with me, took the label off the cask and put it carefully in my pocket, replacing it with one addressed to Jacques de Belleville at the Gare du Nord. As you know, this Jacques de Belleville was myself.

‘As you found Dubois, the carter, you will have learnt the method by which I exchanged the casks, sending that containing the body from my house to Felix, while the other, which I had emptied in London, went back to Dupierre. You understand that part of it?’

‘Perfectly.’

‘So much then for the getting of the body to Felix. But it was my desire not only to give him the shock of opening the cask and discovering it; I wished also to make the police suspicious so that he would be watched and his attempts to get rid of the corpse discovered. In this case I intended he should be charged with the murder, incidentally clearing me. To ensure this result I set myself to construct such evidence as would weave a net round him from which he would be unable to escape. Gradually the details of my plan arranged themselves in my mind.

‘Firstly, it was necessary that I should really have the letter of farewell, the envelope of which I had prepared, and which I had pretended to find on going to my study. Collecting a number of specimens of my wife’s handwriting from her davenport, I forged the