The Billionaire caught sight of him, just as the car slowed to take the sharp turn by the station.  Instant recognition followed.  Flint’s eyes narrowed sharply.

“Hm!  The same fellow,” he grunted to himself.  “The same rascal who stood beside us on the ferry boat, as we were talking over our plans.  Now, what the devil?”

Shadowed by a kind of instinctive uneasiness, not yet definite or clear but more in the nature of a premonition of trouble, Flint gazed fixedly at the mechanic as the car swung round the bend in the road.  The glance was returned.

Yielding to some kind of imperative curiosity, the Billionaire leaned over the side of the car—­leaned out, with his coat flapping in the stiff wind—­and for a moment peered back at the disquieting workman.

Then the car swept him out of sight, and Flint resumed his seat again.

He did not know—­for he had not seen it happen—­that in that moment the slippery, leather-covered note-book had slid from his lolling coat pocket and had fallen with a sharp slap on the white macadam, skidded along and come to rest in the ditch.

The workingman, however, who had paused and turned to look after the speeding car, he had seen all this.

A moment he stood there, peering.  Then, retracing his steps with resolution he picked up the little book and slid it into the pocket of his jeans.

Deserted was the road.  Not a soul was to be seen, save the crossing flagman, musing in his chair beside his little hut, quite oblivious to everything but a rank cob pipe.  The workman’s act had not been noticed.

Nobody had observed him.  Nobody knew.  Not a living creature had witnessed the slight deed on which, by a strange freak of fate, the history of the world was yet to turn.

CHAPTER VIII.

ONE UNBIDDEN, SHARES GREAT SECRETS.

Immediately on discovering his loss—­which was soon after having reached his office—­Flint, in something like a fright, telephoned down to the Oakwood Heights laboratory and instructed Herzog, in person, to make a careful search for it and to report results inside an hour.  Even though some of the essentials of his plan were written in a code of his own devising, Flint paled before the possible results should the book fall into the hands of anybody intelligent enough to fathom its meaning.

“Damn the luck!” he ejaculated, pacing the office floor, his fists knotted.  “If it had been a pocket book with a few thousand inside, that would have been a trifle.  But to lose my plan of campaign—­God grant no harm may come of it!”

Waldron, slyly observing him, could not suppress a smile.

“Calling on God, eh?” sneered he.  “You must be agitated.  I haven’t heard that kind of entreaty on your lips, Flint, since the year of the big coal strike, when you prayed God the gun-men might ‘get’ the strikers before they could organize.  Come, come, man, brace up!  Your book will turn up all right; and even if it doesn’t there’s no cause for alarm.  It would take a man of extraordinary acumen to read your hieroglyphics!  Cheer up, Flint.  There’s really nothing to excite you.”