“Then you think that Ardsley may be . . .”

“There’s a law of libel, Squire; and you’re just twittering on the edge of it at present. I tell you bluntly that I have no definite ideas just now; and you’ll get nothing by all this hydraulic pump business that you’re trying. If I ever get to the bottom of this affair, I promise you I’ll spout like an artesian well of information. Till then, the borings will show no results.”

Wendover accepted the rebuff placidly. Sir Clinton was grateful, and showed it by his next words.

“The fact is, squire, I’m keeping an open mind and I don’t want to be prejudiced. It’s as clear as print that you dislike this man Ardsley. Hence it wouldn’t pay me to listen to you unconsciously discrediting him beforehand. I tell you what. We’ll discuss the thing to-night when I’ve got my mind cleared up a bit; and then you can say what you like. But I don’t promise to give you much information, remember. I’m paid to keep my mouth shut so long as a quiet tongue is necessary; and I’ve got to earn my pay, you see.”

Wendover’s face cleared when this point of view was put before him.

“You can’t put it fairer than that, Clinton,” he admitted. “I hadn’t looked at it quite in that light, you know.”

He said no more at the time, and soon the car reached the entrance to the toxicologist’s grounds. At the house they learned that Dr. Ardsley was at home; and they were shown into a room. He did not keep them waiting long.

As he came forward to meet them, Sir Clinton saw a man of about fifty. Ardsley’s hair was silvered, and his face showed heavy lines; but his step was light and he was obviously in perfect condition. From below heavy eyebrows his grey eyes seemed to examine the world coldly; and the set of his mouth was sufficient to show more than a little toughness in the disposition which had moulded it.

Sir Clinton rapidly explained the cause of his visit; and producing the box of darts, he handed one of them to the toxicologist.

“I’m not sufficiently ignorant to expect you to tell me what this stuff is on the spur of the moment, Dr. Ardsley; but I’m really trusting to luck that you may be able to make a guess at what the thing might be. If you can do even that, it may be of great importance to us.”