the seamen perceived the danger of their position, and arrested their
vessel's course. And that not a moment too soon. She lay-to about a
gunshot from the tower, and presently hoisted the Russian colours. In
response, the Master of the tower at once saluted her by running up
the corresponding flag.

The vessel's long-boat was now lowered. The Commodore, a midshipman,
and four and twenty marines and seamen took their places. All were
fully armed.

They steered for the entrance facing the sea. Although well concealed,
they had soon discovered it with the aid of their powerful glasses.
They succeeded in making their way safely through all the rocks and
breakers which threatened their approach.

The strangers were received at the lower door by an old, hunch-backed
porter, who was, to all appearance, nearly stone deaf. The Commodore
had to shout with all his might into the fellow's ears before he could
be made to hear anything. Then he gave an answer of which not a word
could be understood, for the old man spoke the purest Platt-Deutsch.
By means of signs, however, he at length gave them to understand that
he was the only servant in the establishment, and that if the
gentlemen would like to speak to any one they might go upstairs and
see "Mynheer."

[Illustration]

The Commodore ordered his men to land, and the entire company then
followed the old porter. At each door which they passed on their way
the officer took the precaution of stationing two armed men. When he
reached the observatory floor only the coxswain and the
midshipman--the latter quite a lad--remained with him. But these were
evidently more than sufficient. For the Master of the tower was quite
alone in his study and had beside him no other weapons than those of
science.

The Commodore saluted him in good French:

"You are the Master of this tower, I believe?"

"At present, indeed, I am."

"And for what purpose did you have it built, pray?"

The Master glanced sharply at his questioner.

"May I first inquire," said he, "what entitles you to ask such a
question?"

"You shall hear," replied the officer. "You see, of course, by my
uniform that I am Commodore on a ship of the line in the service of
his Majesty the Tsar of all the Russias. The three-decker lying out
there is my vessel the _St. Thomas_. Of late years an enormous number
of ships have been lost in the Baltic, and that in the most mysterious
circumstances. I have therefore received orde