me, Miss Sartoris. Let
us leave together. It will be better for you that way."

"No," Mary said gently. "I am greatly obliged to you, but I shall stay."

"Both stay, please," Field said in a gentler tone. "Mr. Ventmore, let me
make you the most handsome apology in my power. I am afraid that this
thing has got a little on my nerves. You see, this is a great case, a
far greater case than anybody is aware of. I only stumbled on the real
truth of it more or less by accident to-day. And if there is anything
like a struggle, your help may be of value."

Mark let the matter pass. He could quite understand Field's feeling.
Another quarter of an hour slipped away; the road was now quite
deserted, so that the wheels of a coming cab could be heard a long way
off. There was a little discussion between the cabman and his fare,
followed by the banging of a door, and the heavy footsteps came
staggering up the street and a big man passed before the gate of No.
100, Audley Place. With a sign, Field motioned his companion to steal
behind the bushes.

"One of our birds, unless I am greatly mistaken," he said. "Yes, he is
coming this way."

Mary held her breath now, for she did not fail to recognise the
newcomer. She could see from a casual glance that it was Bentwood.

He came with a lurch and a stagger which proved his condition. He seemed
a little suspicious at first, but the silence of the house, the steady
gleam of the light over the fanlight, seemed to dispel any suspicions.
Then he advanced more boldly to the door. As he stood on the bottom
step, Field emerged from his hiding-place.

"Doctor Bentwood," he said, "I fancy I am not mistaken. You will oblige
me by taking your hand off the bell. Nobody will answer your ring."

Taken aback for a moment, Bentwood stepped off the path. He bent and
gripped Field by the throat.

"You little beast!" he hissed. "I'll kill you. If you only knew who you
are talking to!"

But Field was made of whipcord and steel. He slipped away from the
other's grip and planted two or three body blows that caused Bentwood to
groan aloud. Mark stepped out at once, but there was no need of his
services. Field was all over his man by this time. As he clenched and
drove his left home, Bentwood came heavily to the ground. Before he
could stagger to his feet again, Field had the handcuffs on him.

"It's an outrage," Bentwood blustered, though his face was white now and
his big red cheeks shook like a jelly