“What—­what is the matter with the young lady?” asked Uncle Ith, in great trepidation.  “Shall I run for a doctor?”

“No, Uncle Ith; no doctor.  But we won’t talk any more about this strange room at present.  It affects Miss Wilkeson’s nerves.”

“The shock is past, dear Bog,” said she, “and I can bear to hear everything.”

“But you must promise to control yoursell, darling,” said Bog, tenderly.

“One question, Uncle Ith,” said he.  “How long a time were your eyes off the room, after the first stroke for the Seventh District?”

“Not more than three seconds.”

“And you are sure that there was nobody in the room?”

“Certain; for I must have seen him enter, or go out.”

“Then, Uncle Ith, you have cleared up a great mystery.”

“What!  What mystery?”

“The death of Mr. Minford, the inventor, my old friend, and the protector and guardian of Miss Wilkeson.  He lived in that very room!  He was at work on a perpetual-motion machine!  It was operated, somehow, by weights!  It started suddenly, when you saw that rod, or lever, fall to the floor!  Mr. Minford put the rod in its place, and made some little improvement in the works!  The machine started again at a moment when your eyes were turned away!  The rod fell with greater violence, struck the inventor on the head, and killed him!  That is the whole story; and stupid we have all been not to have guessed it before.”

Nature furnished her own sweet relief to Pet’s pent-up emotions.  She burst into tears.  “Thank Heaven,” said she, “it is all plain now!”

Pet had not whispered it to Mrs. Crull, or Bog, or her uncle, or to any other living soul, but the mystery of that awful night had hung over her young mind like a pall, which in vain she had tried to lift.

“What a blockhead I am,” cried Uncle Ith, “not to take the papers!  If I had only taken the papers, now, I should ha’ read all about that affair, and might ha’ guessed that the man who was s’posed to be murdered was the man I had seen workin’ in that room for three years.  Then I should ha’ offered myself as a witness, and might ha’ thrown some light on the business.  I’ll ‘scribe for a paper to-day, instead of trustin’ to hearsay for the news.”

“And a very neglectful fellow was I,” said Bog, “not to have called here and seen you, after that sad affair.  But the truth was, that Pet went to live with her best of friends, Mrs. Crull, and I had no longer a desire to look at the room from your bell tower.  In fact,” Bog added, with a smile, “the tower has not been quite as interesting for two years past as it used to be.  If I had come up here at any time since Mr. Minford’s death, I should probably have told you of the supposed murder, and pointed out those windows to you.  But—­”

“But you forgot all about your old uncle.  Ha!  I understand.  Well, I forgive you, seein’ what there was to ’sturb your recollections.”  Uncle Ith looked affectionately at Pet, who smiled and blushed through her tears.