jacent
countries, while with the fingers of his left hand he combed his heavy
beard.

From the window he looked down upon the inner fortifications of
Mainz--to which city the capital had been removed three months
before--and upon the landing stage for the scouting planes which were
constantly arriving or whirring off toward Holland or Strassburg. Across
the river, under the concealed guns of a sunken battery, stood the huge
hangars of the now useless dirigibles Z^{51~57}. The landing stage
communicated directly by telephone with the adjutant's office, an
enormous hall filled with maps, with which Von Helmuth's private room
was connected. The adjutant himself, a worried-looking man with a bullet
head and an iron-gray moustache, stood at a table in the centre of the
hall addressing rapid-fire sentences to various persons who appeared in
the doorway, saluted, and hurried off again. Several groups were
gathered about the table and the adjutant carried on an interrupted
conversation with all of them, pausing to read the telegrams and
messages that shot out of the pneumatic tubes upon the table from the
telegraph and telephone office on the floor below.

An elderly man in rather shabby clothes entered, looking about
helplessly through the thick lenses of his double spectacles, and the
adjutant turned at once from the officers about him with an "Excuse me,
gentlemen."

"Good afternoon, Professor von Schwenitz; the general is waiting for
you," said he. "This way, please."

He stalked across to the door of the inner office.

"Professor von Schwenitz is here," he announced, and immediately
returned to take up the thread of his conversation in the centre of the
hall.

The general turned gruffly to greet his visitor. "I have sent for you,
Professor," said he, without removing his cigar, "in order that I may
fully understand the method by which you say you have ascertained the
place of origin of the wireless messages and electrical disturbances
referred to in our communications of last week. This may be a serious
matter. The accuracy of your information is of vital importance."

The professor hesitated in embarrassment, and the general scowled.

"Well?" he demanded, biting off the chewed end of his cigar. "Well? This
is not a lecture room. Time is short. Out with it."

"Your Excellency!" stammered the poor professor, "I--I----The
observations are so--inadequate--one cannot determine----"

"What?" roared Von Helmuth. "Bu