"We've a long wait," commented Ferret. "Fortunately I know several of
the Customs officials very well. I'll get them to let you take shelter
in their shed. It's almost opposite the berth where the steamer
generally makes fast. You'll be able to watch everyone who goes up the
gangway. I'll go on board and speak to the steward. I don't suppose
we'll spot friend von Ruhle until the boat train arrives, and by that
time perhaps Hawke will have marked his man."

Undoubtedly, the wisest course would have been to send other officers
to Wellington to arrest Dr. Ramblethorne; but Hawke was out for
"kudos". Only a short while ago he had let a wanted man slip through
his fingers, and had been rapped over the knuckles for it. With the
professional assistance of Ferret, he hoped to carry out a double
_coup_ and arrest both German Secret Service agents, thereby recovering
his lost prestige.

Arriving at Liverpool Street he took his ticket, and spent the time
until the departure of the boat train in walking up and down the
platform. He had the knack of observing without being observed. He
would look at a man in quite a casual way; there was no gleam of
intelligence in his eyes as he did so, but little escaped his notice.
An hour or two later he could accurately describe his appearance,
dress, and mannerisms.

A minute before the train started, a man answering von Ruhle's
description hurried down the platform. He carried a new cane under his
left arm. In his right hand he held an attache case with the initials
C. V.

Hawke waited until he had entered a carriage, then strolled to the
other end of the corridor coaches and took his seat. He knew that the
run was supposed to be a non-stop one.

The train started. The detective took his time. He waited for nearly
twenty minutes before he made his way along the corridor, and entered
the smoking-compartment occupied by the suspect.

Presently Hawke made a commonplace remark. The stranger replied
stiffly and in rather a deep voice, with a slight foreign accent.

"An assumed voice," soliloquized the detective; but undaunted by the
chilliness of his reception he again made some remark about the weather.

Before the train ran through Witham station, conversation was
proceeding briskly. Hawke assumed the role of a commercial traveller,
and volunteered the information that his brother had just returned from
the Front.

The stranger showed no hesitation in discussing th