“Have you eaten dinner?” questioned the professor.
“No, sir,” replied Harry.
“Crawford will cook you something. Go with him. He will introduce you to Marsh — my other man.
“We have no formalities here, Vincent. If you wish to see me, knock at the outer door; then enter. If I do not hear you, that is my mistake.
“The buzzer on my desk can be heard in all parts of the house even a short distance outside. Four is your signal.”
He turned to the side of the desk, and made a note on a pad.
“Crawford, one; Stokes, two; Marsh, three; Vincent, four,” he muttered.
The professor again faced Harry.
“Do not leave the island without my permission,” he stated. “That is important. Answer every summons promptly. Is there anything else?”
“What are the salary arrangements?” questioned Harry.