. One--the first--was a queer thump,
thump, thump, which seemed to be both close at hand and yet a thousand
miles away. The second was Joseph Chestermarke's voice in the garden
outside--heard clearly through the open window. He was bidding somebody
to tell a cab-driver to wait for him at the foot of the bridge. The next
minute, Neale heard a key plunged into the outer door--before it turned,
he, following out a scheme which he had decided on during his long
watch, had leaped behind the screen that stood near the furnace. Ere the
door could open, he was safely hidden--and in that second he heard the
thumping repeated and knew that it came from the inner room.

The electric light blazed up as Joseph Chestermarke strode in. He put
the door to behind him without quite closing it, and walked into the
middle of the laboratory, feeling in his waistcoat pocket for something
as he advanced. And Neale, peering at him through the high screen, felt
afraid of him for the first time in his life. For the junior partner had
shaved off his beard and moustache, and the face which was thus clearly
revealed, and on which the bright light shone vividly, was one of such
mean and malevolent cruelty that the watcher felt himself turn sick with
dread.

Joseph went straight to the door in the far wall, unlocked it with a
twist of the key which he had brought from his pocket, and walked in.
The click of an electric light switch followed, and Neale stared hard
and nervously into the hitherto hidden room. But he saw nothing but
Joseph Chestermarke, standing, hands planted on his sides, staring at
something hidden by the door. Next instant Joseph spoke--menacingly,
sneeringly.

"So you're round again after one of your long sleeps, are you?" he said.
"That's lucky! Now then, have you come to your senses?"

Neale thought his heart would burst as he waited for the unseen man's
voice. But before he heard any voice he heard something which turned his
blood cold with horror--the clanking, plain, unmistakable, of a chain!
Whoever was in there was chained!--chained like a dog. And following on
that metallic sound came a weary moan.

"Come on, now!" said Joseph. "None of that! Are you going to sign that
paper? Speak, now!"

It seemed to Neale an age before an answer came. But it came at
last--and in Horbury's voice. But what a changed voice! Thin, weak,
weary--the voice of a man slowly being done to death.

"How long are you going to keep me here?" i