ch paralleled track No. 1, he saw a private car, switched
from a Boston and Albany train, shunted to the rear of the Merchants'
Express.

The private car was lettered in gold on the central panel, "Algonquin."
He boarded the Pullman coupled to it forward, pushed through the
vestibule, shoved aside the Japanese steward and darky cook, forcing his
way straight into the private car. Quarrier, reading a magazine,
looked up at him in astonishment. For a full moment neither spoke.
Then Mortimer dropped his suit-case, sat down in an armchair opposite
Quarrier, and leisurely mopped his reeking face and neck.

"Scotch and lithia!" he said hoarsely; the Japanese steward looked at
Quarrier; then, at that gentleman's almost imperceptible nod, went away
to execute the commission.

He executed a great many similar commissions during the trip to New
York. When they arrived there at five o'clock, Quarrier offered Mortimer
his hand, and held the trembling, puffy fingers as he leaned closer,
saying with cold precision and emotionless emphasis something that
appeared to require the full concentration of Mortimer's half-drugged
faculties.

And when at length Mortimer drove away in a hansom, Quarrier's Japanese
steward went with him--perhaps to carry his suit case--a courtesy that
did credit to Quarrier's innate thoughtfulness and consideration
for others. He was very considerate; he even called Agatha up on the
telephone and talked with her for ten minutes. Then he telephoned to
Plank's office, learned that Harrington was already there, telephoned
the garage for a Mercedes which he always kept ready in town, and
presently went bowling away to a conference on which the last few hours
had put an entirely new aspect.

It had taken Plank only a few minutes to perceive that something had
occurred to change a point of view which he had believed it impossible
for Quarrier to change. Something had gone wrong in his own careful
calculations; some cog had slipped, some rivet given way, some bed-plate
cracked. And Harrington evidently had not been aware of it; but Quarrier
knew it. There was something wrong.

It was too late now to go tinkering in the dark for trouble. Plank
understood that. Coolly, as though utterly unaware that the machinery
might not stand the strain, he started it full speed. And when he
stopped it at last Harrington's grist had been ground to atoms, and
Quarrier had looked on without comment. There seemed to be little mor