Then, with half an hour to wait, he lumbered into the buvette and gorged, while Lanyard—­having secured his own transportation for Lyons by the some route—­skulked in the offing and kept a close eye on the gourmand.

Having eaten ferociously, Dupont came out, slouched into a seat on a bench and, his thick limbs a-sprawl, consumed cigarette after cigarette in most absolute abstraction of mind.

Observed thus, off his guard and at tolerably close range, with his face clean of soot, he projected a personality so forbidding that Lanyard marvelled at the guilelessness which must have influenced the ladies of Chateau de Montalais to accept the man at his own valuation and give him a place in their household.

The face of fat features was of porcine cast; the forehead low and slanted sharply back into bristles of black hair, the snout long and blunt, the lips flabby, the chin retreating, the jowls pendulous; the eyes a pig’s, little, cunning, and predaceous; the complexion sallow and pimply from unholy living, with an incongruous over-layer of sunburn.  A type to inspire distrust, one would think, at sight; a nature as repellant as a snake’s, and ten times as deadly; in every line and lineament, in every move and gesture, an Apache of the Apaches...

As for the baleful reflections with which Dupont was patently concerned to the exclusion of all considerations of either surveillance or environment, Lanyard found himself so inquisitive that he had never a thought but to follow and study the fellow till he surprised his secret, if possible—­at least so long as it might seem safe to do so.

Moreover, nothing could have suited his own purpose better than to proceed to Paris by way of Lyons.

Nothing hindered the carrying out of his design.  Still lost in thought and inattentive, Dupont entrained for Nimes and at that station changed to the rapide for Lyons, where duly at four o’clock—­with Lanyard still a discreet shadow—­he alighted in the Gare de Perrache.

Here again fortune favoured the voluntary sleuth.  The station was well thronged, a circumstance which enabled him to keep inconspicuously close to his victim.  Furthermore, Dupont was obviously looking for somebody, and so distracted.  Presently a shabby, furtive little rat of a man nudged his elbow, and Dupont followed him to a corner, where they confabulated in undertones for many minutes; while Lanyard loitered just outside their normal range of vision.  An unnecessary precaution:  they were unafraid of observation, interested only in their private concerns.  The little man did most of the talking; Dupont seeming content with a listening role, and gratified by what he heard.  He nodded frequently, and once or twice a grim smile enhanced the ugliness of his mouth, a smile terrible in its contained savagery, fit to make one’s blood run cold, that cruelly relished in anticipation the success of some evil scheme.

Not to be able to hear a word was exasperating to a degree....