came to him, but it was a plan so
fraught with the possibility of failure that he would not have decided
on it except for the agony of the strain on his thumbs.

Directly opposite him and at a distance of four or five feet was a door
leading to a back alley. This door the emissary now guarding him had
locked as a precaution against surprise and had carefully placed the key
in his vest pocket.

Locke weighed each detail of his plan and then, bracing his feet firmly
against the wall, he suddenly shot his lower limbs forward and, like the
closing of a pair of giant shears, he wrapped his legs about the neck of
the emissary and immediately exerted enormous pressure with his knees.

The emissary, taken totally by surprise, struggled to break the hold,
and Locke's thumbs were almost wrenched from their sockets. But he held
on grimly. Soon the thug's struggles subsided, Locke released him, and
he slipped to the floor.

Locke was wearing a low-cut shoe. Strange that a man's life may hinge on
such a slight detail, but this fact enabled him to work off his right
shoe and his sock. He extended his bare foot, and with his toes searched
the pocket of the emissary for the key to the door. Finally he found it.

Locke held the key as firmly as he might between his toes and,
projecting his body by a muscular effort far away from the wall, he
managed to insert the key in the lock. He turned it. The door was
unlocked now. A swift downward movement of his foot against the knob and
the door swung open.

He braced himself against its edge and, with his back firmly pressed
against the wall, relieved the strain on his thumbs. He rested a moment
and then, as it were, walked up the edge of the door until his feet
reached the top. Swinging one leg over the door, by patient effort he
was enabled to release one swollen thumb, then the other. An instant
later he dropped down and leaned exhaustedly against the wall.

While Locke was held in the room things had happened which would have
set him nearly crazy with anxiety. Eva, having heard nothing from him,
had become alarmed and had telephoned to the chemist. This was at
quarter to five, and she had supposed that it was the chemist who
answered her. In reality it had been an emissary, and he had told her
that the final experiment to find an antidote for her father's malady
had been really a failure and that Locke had left some time before.

After all that she had endured, this was almost the