which broke the
stillness. At the end of five minutes, they came to what was apparently
a deserted shed. Its door was secured by a heavy hasp and padlock.
Crochard drew a key from his pocket, opened the padlock, released the
hasp, and threw back the door.

"Enter, my friends!" he cried, and stood aside that they might pass.

They crowded in and stood staring about them. For a moment, in the
semi-darkness, they could see nothing; then certain vague shapes
detached themselves--a table, a chair, strange jars, a queer-looking
clock....

Marbeau uttered a sudden startled exclamation.

"Why, this is a wireless plant!" he cried.

"Precisely, sir!" agreed Crochard. "The plant from which came those
peculiar signals!"

CHAPTER VII

THE HUT IN THE GROVE

General Marbeau bent with the interest of an expert above the rude table
on which the apparatus was installed, and examined it for some moments
in silence. Then he straightened up and glanced at Delcasse.

"Well?" asked the latter.

"It is, indeed, a wireless installation, sir," said Marbeau, "or, at
least, part of one. Most of the instruments of transmission are here,
but there are no recording instruments. In other words, wireless
messages might be sent from here, but none could be received--unless
this is a recorder of some sort," and he pointed to a small instrument
of clock-like appearance which stood on the table.

"No," said Crochard; "that is not a recorder--that is the sender."

"The sender?" repeated Marbeau.

"Yes. You have noticed there is no key?"

"Yes, and I do not understand its absence."

"This device takes the place of it--it was by means of this that the
spaced signals were sent. Listen."

He bent above the clock, and the others heard a sound as of a strong
spring being wound. Then he stood erect: there were two sharp ticks;
then a long white snap of electricity; two ticks and another snap; two
ticks and another snap....

"Yes, that is the signal!" cried Marbeau, and bent again above the
mechanism. In a moment he understood.

Before the clock-face was a single long hand, a second-hand, terminating
in a thin, spring-like strip of platinum. The circumference of the face
was divided into sixty spaces, and at every third space was a slender
copper pin, which the end of the second-hand touched in passing. Two
wires, one connected with the second-hand, the other presumably with the
copper pins, ran from the clock down to the heavy batt