The man sitting opposite was cast in a different mould. He was tall, spare, almost æsthetic. The clean-shaven face, the well-moulded nose and chin hinted at a refinement which his shabby threadbare suit and his collarless shirt freakishly accentuated. Now and again he would raise his deep-set eyes from the book he was reading, survey the absorbed professor with a speculative glance and then return to his reading.
They had sat in silence for the greater part of an hour, when Beale's tap on the door brought the reader round with narrow eyes.
"Expecting a visitor, professor?" he asked in German.
"Nein, nein," rambled the old man, "who shall visit me? Ah yes"—he tapped his fat forefinger—"I remember, the Fräulein was to call."
He got up and, shuffling to the door, slipped back the bolt and turned it. His face fell when he saw Beale, and the man at the table rose.
"Hope I am not disturbing you," said the detective. "I thought you lived alone."
He, too, spoke in the language which the professor understood best.
"That is a friend of mine," said old Heyler uncomfortably, "we live together. I did not think you knew my address."
"Introduce me," said the man at the table coolly.