ofessor? Can you tell as much about it as
you can about the rope and twine?"

Professor Brierly snapped at him:

"Are you trying to be funny, young man? Are you trying to convey
the impression, are you implying that you do not believe what the
microscope showed me when--"

"Pardon me, Professor. I worded my question wrong. No, remarkable
as it sounds, I believe every word you say, of course. But--"

"There is nothing specially remarkable about it, Mr. Hale. The
true value of the microscope in scientific criminal investigation
is just now beginning to be appreciated. The watch, now--" Once
more the puzzled frown that had appeared several times creased his
brows. He continued slowly:

"There is nothing in the watch that places it in or near the farm
or farmyard from which the heavy rope, the twine and the fish line
seem to have come. There is certainly nothing that places it in a
department of a hat factory where dyed particles of felt hats may
be found in great profusion."

"You mean, Professor," broke in McCall, "that a microscopic
examination of the watch didn't show those characteristics?"

"Yes."

"Provided, Professor, Boyle is telling the truth about when his
watch was cleaned. If the watch were thoroughly cleaned it would
obscure--"

"Boyle told the truth, or the approximate truth about the time his
watch was cleaned last. The watch shows evidence of that."

"What do you say about, Boyle, Professor?" pursued Jimmy.

"There is not a single shred of evidence against him. As I have
heard you say, Mr. Hale, I would not convict a yellow dog on such
evidence."

"Did you hear his alibi, Professor? It's certainly a flimsy
excuse, if I ever heard one."

"True, it is flimsy. But I am half inclined to believe it because
it is so flimsy. I watched him very carefully, as you no doubt
did. I was impressed with the belief that the charge of murder
surprised him. And it did not appear the surprise of a murderer
who thought he had his trail well hidden.

"Boyle is rather above the average criminal. The murderer as we
have seen, is a man of considerable resource. If caught, he is
certain to have a better alibi than Boyle had, a more plausible
alibi. Does Boyle strike you like the kind of man who, if he
murdered a man, would not have a more plausible story? No, I tell
you, its very lack of plausibility almost convinces me of its
truth.

"Boyle is in a desperate situation and he knows it. He showed it
by readily