he devil does he mean?" he muttered.

The Professor's arms shot suddenly above his head. Again that strange,
animal look convulsed his features. He burst into a loud, unnatural laugh.

"Mean, you fool?" he cried, holding out his wrist, which was slowly
turning black. "Poisoned! That is what it means!"

They all stared at him. Quest seized the ink bottle, revealed the false
top and laid it down again with a little exclamation. Then, before they
could realize it, the end came. The Professor lay, a crumpled-up heap,
upon the floor. The last change of all had taken place in his face. His
arms were outstretched, his face deathly white, his lips faintly curved in
the half amiable, half supercilious smile of the savant who sees beyond.
Quest stooped over him.

"He is dead," he declared.

* * * * *

Quest swung round in his chair as French entered the room, and held out
his left hand.

"Glad to see you, French. Help yourself to a cigar."

"I don't know as I want to smoke this morning just at present, thank you,"
French replied.

Quest laid down his pen and looked up. French was fidgeting about with his
hat in his hand. He was dressed more carefully than usual, but he was
obviously ill at ease.

"Nothing wrong, eh?"

"No, there's nothing wrong," French admitted. "I just looked in--"

Quest waited for a moment. Then he crossed his legs and assumed a patient
attitude.

"What the dickens did you look in for?" he asked.

"The fact of it is," French explained, "I should like a few words with
Miss Laura."

Quest laughed shortly.

"Why on earth couldn't you say so?" he observed. "Never knew you bashful
before, Inspector. She's up in the laboratory. I'll ring for some one to
show you the way."

Quest touched the bell and his new secretary entered almost at once.

"Take Inspector French up into the laboratory," Quest directed. "See you
later, French."

"Yes--perhaps--I hope so," the Inspector replied nervously.

Quest watched him disappear, with a puzzled smile.

Then he sat down at his desk, drew a sheet of paper towards him and began
to write:

"My dear Inspector,

"I am taking this opportunity of letting you know that out of
deference to the wishes of the woman I hope soon to marry, I am
abandoning the hazardous and nerve-racking profession of
criminology for a safer and happier career. You will have,
therefore, to find help elsewhere in the future.