“How do you mean if things go right?” asked the detective.

“Well, if I can perfect the electric lathe I am trying to patent,” was the answer.

“Oh, so that’s what King heard about an electric lathe?”

“I suppose so.  It’s no great secret.  I’ve been working on it for some time, but my cousin objected to my spending my time that way.  She thought I should devote it all to her interests, even outside the shop.  I told her I had my own future to look to, and we often had words about that.  Last night’s quarrel wasn’t the first, though she was especially bitter over my work on the lathe.  I have been giving it more time than usual because it is nearly finished, and I want to get it ready to show at a big Eastern jewelry convention.”

“And what was the talk about money?”

“Well, Mrs. Darcy owed me about a thousand dollars.  I had done some special work on making necklaces for her customers, and she had promised, if they were pleased, to pay me extra for the exclusive designs I got up.  The customers were pleased, and they paid her extra for the ornaments.  So I demanded that she keep her promise, but she refused, pleading that many other customers owed her and times were hard.  I needed that thousand dollars to help complete my lathe model, and—­well, we had words over that, too.”

“Then, do I understand,” summed up Carroll, “that the night Mrs. Darcy was killed you had a quarrel with her over Miss Mason, and about the money and because you spent too much time working on your patent lathe?”

“Well, yes, though I don’t admit I spent too much time, and I surely will claim she owed me that money.  As for Miss Mason—­I’d prefer to have her name left out,” faltered the young jeweler.

“We can’t always have what we want,” said Thong, dryly.  “Was the quarrel specially bitter?”

“Not any more so than others.  I had to speak a little loud, for my cousin was getting a trifle deaf.”

“And after the quarrel you went to bed?”

“Yes.”

“And you didn’t see your cousin again until—­when?” and Carroll looked Darcy straight in the eyes.

“Not until after she was—­dead.”

“Um!  I guess that’s all now.”

They let the young man go, back to his room in police headquarters.  It was not a cell—­yet, though it would seem likely to come to that, for Thong observed to his partner as they went downstairs: 

“Well, there’s a motive all right.”

“Three, if you like.  But none of ’em hardly strong enough for murder.”

“Oh, I don’t know.  I hear he has quite a temper—­different from Harry King’s, but enough, especially if he got riled about the old lady talking against his girl.  You never can tell.”

“No, that’s so.”

Left alone, James Darcy threw himself into a chair and looked blankly at the dull-painted wall.

“This is fierce!” he murmured.  “It will be a terrible blow to Amy!  I wonder—­I wonder if she’ll have anything to do with me after this?  The shame of it—­the disgrace!  Oh, Amy! if I could only know!” and he reached out his hand as though to thrust them beyond the confines of the walls.  He bowed his head in his arms and was silent and motionless a long time.