“This is an important piece of evidence,” said he. “I wish we were able to take casts, but the notes will be pretty conclusive. And now,” he continued as we resumed our progress towards the station, “to return to your question. Parton’s evidence at the inquest proved that Cyrus Pedley was drowned in water which contained duck-weed. He produced a specimen and we both saw it. We saw the duck-weed in it and also two Planorbis shells. The presence of those two shells proved that the water in which he was drowned must have swarmed with them. We saw the body, and observed that one hand grasped a wisp of horn-weed. Then we went to view the ditch and we examined it. That was when I got, not a mere hint, but a crucial and conclusive fact. The ditch was covered with duck-weed, as we expected. _But it was the wrong duck-weed._” “The wrong duck-weed!” I exclaimed. “Why, how many kinds of duck-weed are there?” “There are four British species,” he replied. “The Greater Duck-weed, the Lesser Duck-weed, the Thick Duck-weed, and the Ivy-leaved Duck-weed. Now the specimens in Parton’s jar I noticed were the Greater Duck-weed, which is easily distinguished by its roots, which are multiple and form a sort of tassel. But the duck-weed on the Bantree ditch was the Lesser Duck-weed, which is smaller than the other, but is especially distinguished by having only a single root. It is impossible to mistake one for the other. “Here, then, was practically conclusive evidence of murder. Cyrus Pedley had been drowned in a pond or ditch. But not in the ditch in which his body was found. Therefore his dead body had been conveyed from some other place and put into this ditch. Such a proceeding furnishes _prima facie_ evidence of murder. But as soon as the question was raised, there was an abundance of confirmatory evidence. There was no horn-weed or Planorbis shells in the ditch, but there were swarms of succineæ, some of which would inevitably have been swallowed with the water. There was an obscure linear pressure mark on the arm of the dead man, just above the elbow: such a mark as might be made by a cord if a man were pinioned to render him helpless. Then the body would have had to be conveyed to this place in some kind of vehicle; and we found the traces of what appeared to be a motor-van, which had approached the cart-track on the wrong side of the road, as if to pull up there. It was a very conclusive mass of evidence; but it would have been useless but for the extraordinarily lucky chance that poor Pedley had lost his railway ticket and preserved the receipt; by which we were able to ascertain where he was on the day of his death and in what locality the murder was probably committed. But that is not the only way in which Fortune has favoured us. The station-master’s information was, and will be, invaluable. Then it was most fortunate for us that there was only one ditch on the factory land; and that that ditch was accessible at only one point, which must