Mr. Saul Arthur Mann stood by the window of his office and moodily watched the traffic passing up and down this busy city street at what was the busiest hour of the day. He stood there such a long time that the girl who had sought his help thought he must have forgotten her.

May was pale, and her pallor was emphasized by the black dress she wore. The terrible happening of a week before had left its impression upon her. For her it had been a week of sleepless nights, a week's anguish of mind unspeakable. Everybody had been most kind, and Jasper was as gentle as a woman. Such was the influence that he exercised over her that she did not feel any sense of resentment against him, even though she knew that he was the principal witness for the crown. He was so sincere, so honest in his sympathy, she told herself.

He was so free from any bitterness against the man who he believed had killed his best friend and his most generous employer that she could not sustain the first feeling of resentment she had felt. Perhaps it was because her great sorrow overshadowed all other emotions; yet she was free to analyze her friendship with the man who was working day and night to send the man who loved her to a felon's doom. She could not understand herself; still less could she understand Jasper.

She looked up again at Mr. Mann as he stood by the window, his hands clasped behind him; and as she did so he turned slowly and came back to where she sat. His usually jocund face was lugubrious and worried.

"I have given more thought to this matter than I've given to any other problem I have tackled," he said. "I believe Mr. Merrill to be falsely accused, and I have one or two points to make to his counsel which, when they are brought forward in court, will prove beyond any doubt whatever that he was innocent. I don't believe that matters are so black against him as you think. The other side will certainly bring forward the forgery and the doctored books to supply a motive for the murder. Inspector Nash is in charge of the case, and he promised to call here at four o'clock."

He looked at his watch.

"It wants three minutes. Have you any suggestion to offer?"

She shook her head.

"I can floor the prosecution," Mr. Mann went on, "but what I cannot do is to find the murderer for certain. It is obviously one of three men. It is either Sergeant Crawley, alias Smith, about whose antecedents Mr. Minute made an inquiry, or Jasper Cole, the secretary, or--"

He shrugged his shoulders.

It was not necessary to say who was the third suspect.

There came a knock at the door, and the clerk announced Inspector Nash. That stout and stoical officer gave a noncommittal nod to Mr. Mann and a smiling recognition to the girl.

"Well, you know how matters stand, Inspector," said Mr. Mann briskly, "and I thought I'd ask you to come here to-day to straighten a few things out."

"It is rather irregular, Mr. Mann," said the inspector, "but as they've no objection at headquarters, I don't mind telling you, within limits, all that I know; but I don't suppose I can tell you any more than you have found out for yourself."

"Do you really think Mr. Merrill committed this crime?" asked the girl.

The inspector raised his eyebrows and pursed his lips.

"It looks uncommonly like it, miss," he said. "We have evidence that the bank has been robbed, and it is almost certainly proved that Merrill had access to the books and was the only person in the bank who could have faked the figures and transferred the money from one account to another without being found out. There are still one or two doubtful points to be cleared up, but there is the motive, and when you've got the motive you are three parts on your way to finding the criminal. It isn't a straightforward case by any means," he confessed, "and the more I go into it the more puzzled I am. I don't mind telling you this frankly: I have seen Constable Wiseman, who swears that at the moment the shots were fired he saw a light flash in the upper window. We have the statement of Mr. Cole that he was in his room, his employer having requested that he should make himself scarce when the nephew came, and he tells us how somebody opened the door quietly and flashed an electric torch upon him."

"What was Cole doing in the dark?" asked Mann quickly.

"He had a headache and was lying down," said the inspector. "When he saw the light he jumped up and made for it, and was immediately slugged; the door closed upon him and was locked. Between his leaving the bed and reaching the door he heard Mr. Merrill's voice threatening his uncle, and the shots. Immediately afterward he was rendered insensible."

"A curious story," said Saul Arthur Mann dryly. "A very curious story!"

The girl felt an unaccountable and altogether amazing desire to defend Jasper against the innuendo in the other's tone, and it was with difficulty that she restrained herself.

"I don't think it is a good story," said the inspector frankly; "but that is between ourselves. And then, of course," he went on, "we have the remarkable behavior of Sergeant Smith."

"Where is he?" asked Mr. Mann.

The inspector shrugged his shoulders.

"Sergeant Smith has disappeared," he said, "though I dare say we shall find him before long. He is only one; the most puzzling element of all is the fourth man concerned, the man who arrived in the motor car and who was evidently Mr. Rex Holland. We have got a very full description of him."

"I also have a very full description of him," said Mr. Mann quietly; "but I've been unable to identify him with any of the people in my records."

"Anyway, it was his car; there is no doubt about that."

"And he was the murderer," said Mr. Mann. "I've no doubt about that, nor have you."

"I have doubts about everything," replied the inspector diplomatically.

"What was in the car?" asked the little man brightly. He was rapidly recovering his good humor.

"That I am afraid I cannot tell you," smiled the detective.

"Then I'll tell you," said Saul Arthur Mann, and, stepping up to his desk, took a memorandum from a drawer. "There were two motor rugs, two holland coats, one white, one brown. There were two sets of motor goggles. There was a package of revolver cartridges, from which six had been extracted, a leather revolver holster, a small garden trowel, and one or two other little things."

Inspector Nash swore softly under his breath.

"I'm blessed if I know how you found all that out," he said, with a little asperity in his voice. "The car was not touched or searched until we came on the scene, and, beyond myself and Sergeant Mannering of my department, nobody knows what the car contained."

Saul Arthur Mann smiled, and it was a very happy and triumphant smile.

"You see, I know!" he purred. "That is one point in Merrill's favor."

"Yes," agreed the detective, and smiled.

"Why do you smile, Mr. Nash?" asked the little man suspiciously.

"I was thinking of a county policeman who seems to have some extraordinary theories on the subject."

"Oh, you mean Wiseman," said Mann, with a grin. "I've interviewed that gentleman. There is a great detective lost in him, Inspector."

"It is lost, all right," said the detective laconically. "Wiseman is very certain that Merrill committed the crime, and I think you are going to have a difficulty in persuading a jury that he didn't. You see Merrill's story is that he came and saw his uncle, that they had a few minutes' chat together, that his uncle suddenly had an attack of faintness, and that he went out of the room into the dining room to get a glass of water. While Merrill was in the dining room he heard the shots, and came running back, still with the glass in his hand, and saw his uncle lying on the ground. I saw the glass, which was half filled.

"I was also there in time to examine the dining room and see that Mr. Merrill had spilled some of the water when he was taking it from the carafe. All that part of the story is circumstantially sound. What we cannot understand, and what a jury will never understand, is how, in the very short space of time, the murderer could have got into the room and made his escape again."

"The French windows were open," said Mr. Mann. "All the evidence that we have is to this effect, including the evidence of P. C. Wiseman."

"In those circumstances, how comes it that the constable, who, when he heard the shot, made straight for the room, did not meet............