“We’ll go get some supper—­no, we’ll take little ’scursion in Central Park, first,” and his voice was thick, “correct, cabbie.  Drive us shru Central Park.”

“Are you going to take a chance in a dark park?” Helene asked him, as they sat within the car, while the chauffeur cranked.  Shirley was sharply observing the man.  A pedestrian crossed directly in front of the machine, brushing against the driver, as he fumbled with the lamp.  If there were an interchange of words, the criminologist could not detect it.

“Surely.  The park is good.  We can be free of interference from the police.  Are you afraid?”

“No—­” yet, it was a pardonably weak little voice which uttered the valiant monosyllable.

“Here, Miss Marigold.  Take this revolver.  Don’t use it until you have to, but then don’t hesitate a second.”

The machine started slowly up the street.  Shirley groped about the sides and bottom of the car, to make sure that no one could be concealed within it.  They were advancing up Broadway in leisurely fashion.  It might have been for the purpose of allowing some to follow.  Shirley wondered, then sniffed the air suspiciously.  The girl looked at him with a silent question.

“Quick, tear off your glove and let me have that diamond ring I noticed on your finger, the large solitaire, not the dinner ring.”

Unquestioningly she obeyed.  There was a strange Oriental odor in the car—­suggestive of an incense.  The car was gliding up Central Park West, toward one of the road entrances into the Park proper.  Shirley’s hand clutched the ring, tensely.  The driver, tactfully looking straight to the front, gave no heed to the occupants of the Death Car.  He was, by this time speeding too rapidly for either of his passengers to have leaped out without injury.  Shirley understood the smoothness of the voice’s system, by now.  His hand slid to the top of the glass door pane, on the right.  Down the glass, across the bottom, down from the other corner, and then over the top line, he cut with the diamond, using a peculiar pressure.  He rose to his feet, gave the lower part of the pane a sharp tap.  The glass, practically cut loose from its case, now dropped and would have slid out to the roadway with a crash had he not dexterously caught it, to draw it into the car.  Quickly he repeated the operation with the door pane at the left.  A nauseating, weakening something in the car sent Helene’s head spinning; she choked for breath and lay back weakly, despite her will.  Shirley turned to the small glass square in the rear.  This came out more easily.  He lay the glass with the others, on the floor of the car.  The good clear air whirled through the openings, reviving the girl.

“Keep your eyes open, and that revolver ready.  Now is the time.  Pretend to sleep.”

Shirley had drawn his own automatic by this time, and he realized that the machine was slowing down.  The chauffeur, as they passed a walk light, looked back, observing that the two were apparently unconscious.  He slowed down still more, and tooted his horn three times.  A large touring car passed them, to stop some distance ahead.  Then it sped on, as Shirley’s taxi followed lazily.