. "The injury to yourself
and your assistant. How do you explain that?"

"It was done by John Gilder swinging a sand-bag on a string at the end
of a pole which he poked through one of those panels.

"It couldn't be seen in that dim light, and it made a fearful weapon.
It's a wonder that he didn't knock our heads off."

"I thought that I heard something whiz," muttered Patsy.

"And yet I heard her voice this morning," said the colonel. "She said
'consent.'"

"No, she didn't; I said it," rejoined Nick. "I'm something of a
ventriloquist."

"How was the affair managed at the safe deposit vault?" asked the
colonel, after a pause.

"Why, Horace took the clasp out of the box and put it into your pocket.
You really saw it, only he made you think afterward that you didn't.

"After I had searched him he picked your pocket and got the clasp. Then
he wrapped it in paper.

"I picked his pocket to make matters even, and substituted my knife
similarly wrapped up.

"When we got to this house he gave the knife to Annie O'Neil, who put it
on Miss Stevens' pillow when she went upstairs to call Mrs. Stevens."

"You have not explained the robberies at my house," said Colonel
Richmond.

"I'll do that over there. Is the rest of it clear? Has anybody a
question to ask?"

Nobody spoke.

"Annie O'Neil," said Nick, "I'll leave here in Patsy's charge. Horace
Richmond, come with us."

Horace looked ugly for a moment, and then he calmed down and sullenly
complied with Nick's order.

Judge Lorrimer begged to be of the party in order to see the explanation
of the mysterious robberies of which he had heard.

Two hours later they all stood in Mrs. Pond's room.

"The essential part of this matter," said Nick, "was this door which
appeared to open and close of itself.

"I saw that at a glance, and made a secret investigation. It is done by
electricity.

"There's a magnet in the casing which is powerful enough to swing the
door to, after which the same magnet pushes this little bolt--which
looks like an ordinary screw--into position, and that holds the door,
but not very steadily.

"You may say that this should have given me the criminal at once, but it
didn't.

"You see, this electro-magnet works whenever a current is turned into
the wires. Horace was clever enough to have the wires lead all over the
house.

"A connection with the electric light wires, furnishing the current, can
be made in almost every room in the house.