"I can't tell you, sir—it has been there since I came in."
"H'm—I must have overlooked it. Perhaps it is news from your factory."
He tore it open, scanned the contents and swore.
"There goes your evidence, Beale," he said.
"What is it?" asked Beale quickly.
"The factory was burned to the ground in the early hours of the morning," he said. "The fire started in the old wine vault and the whole building has collapsed."
The detective stared out of the window.
"Can we arrest van Heerden on the evidence of Professor Heyler?"
For answer McNorton handed him the letter. It ran:
"From Inspector-in-charge, S. Paddington, to Supt. McNorton. Factory in Playbury St. under P.O. (Police Observation) completely destroyed by fire, which broke out in basement at 5.20 this morning. One body found, believed to be a man named Heyler."