"On the other hand, a man in Sneathy's state (assuming him, for the moment, to be mad and contemplating suicide) would walk straight along the centre of the path, taking no note of mud or anything else. I examined all the tracks very carefully, and my theory was confirmed. The feet of the brothers had everywhere alighted in the driest spots, and the steps were of irregular lengths--which meant, of course, that they were picking their way; while Sneathy's footmarks had never turned aside even for the dirtiest puddle. Here, then, were the rudiments of a theory. "At the watercourse, of course, the footmarks ceased, because of the hard gravel. The body lay on a knoll at the left--a knoll covered with grass. On this the signs of footmarks were almost undiscoverable, although I am often able to discover tracks in grass that are invisible to others. Here, however, it was almost useless to spend much time in examination, for you and your man had been there, and what slight marks there might be would be indistinguishable one from another. "Under the branch from which the man had hung there was an old tree stump, with a flat top, where the tree had been sawn off. I examined this, and it became fairly apparent that Sneathy had stood on it when the rope was about his neck--his muddy footprint was plain to see; the mud was not smeared about, you see, as it probably would have been if he had been stood there forcibly and pushed off. It was a simple, clear footprint--another hint at suicide. "But then arose the objection that you mentioned yourself. Plainly the brothers Foster were following Sneathy, and came this way. Therefore, if he hanged himself before they arrived, it would seem that they must have come across the body. But now I examined the body itself. There was mud on the knees, and clinging to one knee was a small leaf. It was a leaf corresponding to those on the bush behind the tree, and it was not a dead leaf, so must have been just detached.