It was too dark to see anything.

But he heard the young detective's soft footfalls passing the door and he
stepped out into the hall behind Harry.

Slight as the noise was which he made, the boy heard him and turned around,
striving to pierce the gloom with his sight.

La Croix had the boy located.

He suddenly sprang forward with both hands extended, struck against the
boy, clutched him by the throat and knocked him over backward.

A stifled cry escaped Harry.

He was knocked down and struck the floor with a crash.

As his head went back, with the Frenchman's grip on his windpipe, his skull
banged against the door-casing.

He was stunned.

"Lena! Lena!" roared La Croix.

"What is it, Paul?" asked the woman, appearing in the doorway.

"Breeng a light--queek!" he panted.

She struck a match and he saw that Harry was senseless.