at all,” he replied. “We are engaged in the study of pond and ditch natural history, and a most fascinating and instructive study it is. The variety of forms is endless. This ditch, you observe, like the one at Bantree, is covered with a dense growth of duck-weed: but whereas that ditch was swarming with succinea here there is not a single succinea to be seen.”
I grunted a sulky assent, and watched suspiciously as he filled the bottles with water from the ditch and then made a preliminary sweep with his net.
“Here is a trial sample,” said he, holding the loaded net towards me. “Duck-weed, horn-weed, Planorbis nautileus, but no succinea. What do you think of it, Jervis?”
I looked distastefully at the repulsive mess, but yet with attention, for I realised that there was a meaning in his question. And then, suddenly, my attention sharpened. I picked out of the net a strand of dark green, plumy weed and examined it. “So this is horn-weed,” I said. “Then it was a piece of horn-weed that Cyrus Pedley held grasped in his hand; and now I come to think of it, I don’t remember seeing any horn-weed in the ditch at Bantree.”
He nodded approvingly. “There wasn’t any,” said he.
“And these little ammonite-like shells are just like those that I noticed at the bottom of Dr. Parton’s jar. But I don’t remember seeing any in the Bantree ditch.”
“There were none there,” said he. “And the duck-weed?”
“Oh, well,” I replied,” duck-weed is duck-weed, and there’s an end of it.”
He chuckled aloud at my answer, and quoting: “A primrose by the river’s brim A yellow primrose was to him,” bestowed a part of the catch in the vasculum, then turned once more to the ditch and began to ply his net vigorously, emptying out each netful on the grass, looking it over quickly and then making a fresh sweep, dragging the net each time through the mud at the bottom. I watched him now with a new and very lively interest; for enlightenment was dawning, mingled with some self-contempt and much speculation as to how Thorndyke had got his start in this case.
But I was not the only interested watcher. At one of the windows of the factory I presently observed a man who seemed to be looking our way. After a few seconds’ inspection he disappeared, to reappear almost immediately with a pair of field-glasses, through which he took a long look at us. Then he disappeared again, but in less than a minute I saw him emerge from a side door and advance hurriedly towards us.
“We are going to have a notice of ejectment served on us, I fancy,” said I.
Thorndyke glanced quickly at the approaching stranger but continued to ply his net, working, as I noticed, methodically from left to right. When the man came within fifty yards he hailed us with a brusque inquiry as to what our business was. I went forward to meet him and, if possible, to detain him in conversation; but this plan failed, for he ignored me and bore straight down on Thorndyke.
“Now, then,” said he, “what’s the game? What are you doing here?”
Thorndyke was in the act of raising his net from the water, but he now suddenly let it fall to the bottom of the ditch while he turned to confront the stranger.
“I take it that you have some reason for asking,” said he.
“Yes, I have,” the other replied angrily and with a slight foreign accent that agreed with his appearance—he looked like a Slav of some sort. “This is private land. It belongs to the factory. I am the manager.”
“The land is not enclosed,” Thorndyke remarked.
“I tell you the land is private land,” the fellow retorted excitedly. “You have no business here. I want to know what you are doing.”
“My good sir,” said Thorndyke, “there is no need to excite yourself. My friend and I are just collecting botanical and other specimens.”
“How do I know that?” the manager demanded. He looked round suspiciously and his eye lighted on the vasculum. “What have you got in that thing?” he asked.
“Let him see what is in it,” said Thorndyke, with a significant look at me.
Interpreting this as an instruction to occupy the man’s attention for a few moments, I picked up the vasculum and placed myself so that he must turn his back to Thorndyke to look into it. I fumbled awhile with the catch, but at length opened the case and began to pick out the weed strand by strand. As soon as the stranger’s back was turned Thorndyke raised his net and quickly picked out of it something which he slipped into his pocket. Then he advanced towards us, sorting out the contents of his net as he came.
“Well,” he said, “you see we are just harmless naturalists. By the way, what did you think we were looking for?”
“Never mind what I thought,” the other replied fiercely. “This is private land. You have no business here, and you have got to clear out.”
“Very well,” said Thorndyke. “As you please. There are plenty of other ditches.” He took the vasculum and the case of bottles, and having put them in his pocket, unscrewed his net, wished the stranger “Good-morning,” and turned back towards the station. The man stood watching us until we were near the level crossing, when he, too, turned back and retired to the factory.
“I saw you take something out of the net,” said I. “What was it?”
He glanced back to make sure that the manager was out of sight. Then he put his hand in his pocket, drew it out closed, and suddenly opened it. In his palm lay a small gold dental plate with four teeth on it.
“My word!” I exclaimed; “this clenches the matter with a vengeance. That is certainly Cyrus Pedley’s plate. It corresponds exactly to the description.”
“Yes,” he replied, “it is practically a certainty. Of course, it will have to be identified by the dentist who made it. But it is a foregone conclusion.”
I reflected as we walked towards the station on the singular sureness with which Thorndyke had followed what was to me an invisible trail. Presently I said “What is puzzling me is how you got your start in this case. What gave you the first hint that it was homicide and not suicide or misadventure?”
“It was the old story, Jervis,” he replied; “just a matter of observing and remembering apparently trivial details. Here, by the way, is a case in point.”
He stopped and looked down at a set of tracks in the soft, earth road—apparently those of the van which we had seen cross the line. I followed the direction of his glance and saw the clear impression of a Blakey’s protector, preceded by that of a gash in the tyre and followed by that of a projecting lump.
“But this is astounding!” I exclaimed. “It is almost certainly the same track that we saw in Ponder’s Road.”
“Yes,” he agreed. “I noticed it as we came along.” He brought out his spring-tape and notebook, and handing the latter to me, stooped and measured the distances between the three impressions. I wrote them down as he called them out, and then we compared them with the note made in Ponder’s Road. The measure ments were identical, as were the relative positions of the impressions.
“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
