It was two months after the great trial, on a warm day in October, when Frank Merrill stepped ashore from the big white paddle boat which had carried him across Lake Leman from Lausanne, and, handing his bag to a porter, made his way to the hotel omnibus. He looked at his watch. It pointed to a quarter to four, and May was not due to arrive until half past. He went to his hotel, washed and changed and came down to the vestibule to inquire if the instructions he had telegraphed had been carried out.

May was arriving in company with Saul Arthur Mann, who was taking one of his rare holidays abroad. Frank had only seen the girl once since the day of the trial. He had come to breakfast on the following morning, and very little had been said. He was due to leave that afternoon for the Continent. He had a little money, sufficient for his needs, and Jasper Cole had offered no suggestion that he would dispute the will, in so far as it affected Frank. So he had gone abroad and had idled away two months in France, Spain, and Italy, and had then made his leisurely way back to Switzerland by way of Maggiore.

He had grown a little graver, was a little more set in his movements, but he bore upon his face no mark to indicate the mental agony through which he must have passed in that long-drawn-out and wearisome trial. So thought the girl as she came through the swing doors of the hotel, passed the obsequious hotel servants, and greeted him in the big palm court.

If she saw any change in him he remarked a development in her which was a little short of wonderful. She was at that age when the woman is breaking through the beautiful chrysalis of girlhood. In those two months a remarkable change had come over her, a change which he could not for the moment define, for this phenomenon of development had been denied to his experience.

"Why, May," he said, "you are quite old."

She laughed, and again he noticed the change. The laugh was richer, sweeter, purer than the bubbling treble he had known.

"You are not getting complimentary, are you?" she asked.

She was exquisitely dressed, and had that poise which few Englishwomen achieve. She had the art of wearing clothes, and from the flimsy crest of her toque to the tips of her little feet she was all that the most exacting critic could desire. There are well-dressed women who are no more than mannequins. There are fine ladies who cannot be mistaken for anything but fine ladies, whose dresses are a horror and an abomination and whose expressed tastes are execrable.

May Nuttall was a fine lady, finely appareled.

"When you have finished admiring me, Frank," she said, "tell us what you have been doing. But first of all let us have some tea. You know Mr. Mann?"

The little investigator beaming in the background took Frank's hand and shook it heartily. He was dressed in what he thought was an appropriate costume for a mountainous country. His boots were stout, the woolen stockings which covered his very thin legs were very woolen, and his knickerbocker suit was warranted to stand wear and tear. He had abandoned his top hat for a large golf cap, which was perched rakishly over one eye. Frank looked round apprehensively for Saul Arthur's alpenstock, and was relieved when he failed to discover one.

The girl threw off her fur wrap and unbuttoned her gloves as the waiter placed the big silver tray on the table before her.

"I'm afraid I have not much to tell," said Frank in answer to her question. "I've just been loafing around. What is your news?"

"What is my news?" she asked. "I don't think I have any, except that everything is going very smoothly in England, and, oh, Frank, I am so immensely rich!"

He smiled.

"The appropriate thing would be to say that I am immensely poor," he said, "but as a matter of fact I am not. I went down to Aix and won quite a lot of money."

"Won it?" she said.

He nodded with an amused little smile.

"You wouldn't have thought I was a gambler, would you?" he asked solemnly. "I don't think I am, as a matter of fact, but somehow I wanted to occupy my mind."

"I understand," she said quickly.

Another little pause while she poured out the tea, which afforded Saul Arthur Mann an opportunity of firing off fifty facts about Geneva in as many sentences.

"What has happened to Jasper?" asked Frank after a while.

The girl flushed a little.

"Oh, Jasper," she said awkwardly, "I see him, you know. He has become more mysterious than ever, quite like one of those wicked people one reads about in sensational stories. He has a laboratory somewhere in the country, and he does quite a lot of motoring. I've seen him several times at Brighton, for instance."

Frank nodded slowly.

"I should think that he was a good driver," he said.

Saul Arthur Mann looked up and met his eye with a smile which was lost upon the girl.

"He has been kind to me," she said hesitatingly.

"Does he ever speak about--"

She shook her head.

"I don't want to think about that," she said; "please don't let us talk about it."

He knew she was referring to John Minute's death, and changed the conversation.

A few minutes later he had an opportunity of speaking with Mr. Mann.

"What is the news?" he asked.

Saul Arthur Mann looked round.

"I think we are getting near the truth," he said, dropping his voice. "One of my men has had him under observation ever since the day of the trial. There is no doubt that he is really a brilliant chemist."

"Have you a theory?"

"I have several," said Mr. Mann. "I am perfectly satisfied that the unfortunate fellow we saw together on the occasion of our first meeting was Rex Holland's servant. I was as certain that he was poisoned by a very powerful poisoning. When your trial was on the body was exhumed and examined, and the presence of that drug was discovered. It was the same as that employed in the case of the chauffeur. Obviously, Rex Holland is a clever chemist. I wanted to see you about that. He said at the trial that he had discussed such matters with you."

Frank nodded.

"We used to have quite long talks about drugs," he said. "I have recalled many of those conversations since the day of the trial. He even fired me with his enthusiasm, and I used to assist him in his little experiments, and obtained quite a working knowledge of these particular elements. Unfortunately I cannot remember very much, for my enthusiasm soon died, and beyond the fact that he employed hyocine and Indian hemp I have only the dimmest recollection of any of the constituents he employed."

Saul Arthur nodded energetically.

"I shall have more to tell you later, perhaps," he said, "but at present my inquiries are shaping quite nicely. He is going to be a difficult man to catch, because, if all I believe is true, he is one of the most cold-blooded and calculating men it has ever been my lot to meet--and I have met a few," he added grimly.

When he said men Frank knew that he had meant criminals.

"We are probably doing him a horrible injustice," he smiled. "Poor old Jasper!"

"You are not cut out for police work," snapped Saul Arthur Mann; "you've too many sympathies."

"I don't exactly sympathize," rejoined Frank, "but I just pity him in a way."

Again Mr. Mann looked round cautiously and again lowered his voice, which had risen.

"There is one thing I want to talk to you about. It is rather a delicate matter, Mr. Merrill," he said.

"Fire ahead!"

"It is about Miss Nuttall. She has seen a lot of our friend Jasper, and after every interview she seems to grow more and more reliant upon his help. Once or twice she has been embarrassed when I have spoken about Jasper Cole and has changed the subject."

Frank pursed his lips thoughtfully, and a hard little look c............