udden, the darkness was riven by the screaming note of a police
whistle--of two police whistles in fact: shrilling appeal and answer far
up the lonely lane.

Hard on this came a man's voice shouting: "Head him off there, whoever
you are! Don't let him get by you. Look sharp! He's making for the
railway arch!"

"All right, mate. I'm here!" another male voice flung back. "He won't
get past me, the blighter!"

Instantly there struck out the swift-measured sound of heavily shod feet
racing at top speed up the mist-shrouded lane, and rapidly increasing
the distance between the unseen runner and the standing limousine.

No need to tell either Narkom or his men that the man whose steps they
heard was a constable, for there is a distinctive note, to ears that are
trained, rung out by the heavy, cumbersome boots which folly accords to
the British policeman.

Catching the ring of that telltale note now, Narkom shouted out at the
top of his voice: "All right, Constable! Stick to him! Help coming!"

Then with a word of command to Lennard he pulled in his head, slammed
the door, and the chauffeur, dropping back to his seat, threw open the
clutch and sent the limousine bounding up the lane at a fifty-mile clip.

To-night, with the trees shadowing it and the mist crowding in, shoulder
high, from the adjacent Common, the lane was a mere dark funnel; but to
Lennard, whose boyhood had been passed within hailing distance of the
place, it possessed no mysteries that the night or the vapour could
hide.

He knew that it ran on for some seven or eight hundred feet, with the
high brick wall which marked the rear boundary of Wuthering Grange on
one side of it and straggling trees and matted gorse bushes shutting it
in on the other, until it dipped down a steadily increasing incline, and
ran straightway through an old brick-walled, brick-roofed arch of a
long-abandoned Wimbledon Loop line.

Some two hundred feet upon the other side of this it divided into a sort
of "Y," one branch swerving to the left forming a right of way across
the meadows to the public highway, whilst the other struck out over the
Common to the right, crossed Beverly Brook, and merged at length into
the road which leads to Coombe Wood, and thence, through picturesque
ways, to Kingston and the river.

The limousine took those seven or eight hundred feet between the head of
the lane and the old railway arch at such a stupendous pace that it
seemed to have no more t