As Rhuburger reached the topmost step, the collie lifted his head, his nostrils dilating wide. A thrill went through him. His nearsighted eyes swept the crowd. They rested at last on Rhuburger. Another deep inhalation told him all he needed to know. Not in vain had Lad sniffed so long and so carefully at those faint footprints in the road dust, at the spot where Lady died. In his throat a deep growl was born.

"Hello, folks!" Rhuburger was declaiming, to a wholly unenthusiastic circle of acquaintances. "Made another record, just now. The little boat spun me here from Montclair in exactly nineteen minutes. That's--that's roughly an average rate of a mile in seventy-five seconds. Not so bad, eh? That car sure made a hit with ME, all right. Not so much of a hit, maybe, with a couple of chickens and a fat old dog that had the bad luck to be asleep in the middle of the--"His plangent brag was lost in a sound seldom heard on the hither side of jungle or zoo. From the group of slightly disgusted onlookers, a huge and tawny shape burst forth; hurtling through the air, straight for the fat throat of the boaster.

Rhuburger, by some heaven-sent instinct, flung up his arms to shield his menaced jugular. He had no time to do more.

Lad's fury-driven eighty pounds of muscular weight crashed full against his chest. Lad's terrible teeth, missing their throat-goal, drove deep into the uplifted right forearm; shearing through imported tweed coat-sleeve and through corded silken shirt, and through flabby flesh and clean to the very bone.

The dog's lion-roar blended with the panic-screeches of the victim. And, under that fearful impact, Rhuburger reeled back from the stairhead, and went crashing down the steps, to the broad stone flagging at the bottom.

Not once, during that meteoric, shriek-punctured downward flight, did Lad loose his grip on the torn forearm. But as the two struck the flagging at the bottom, he shifted his hold, with lightning speed; stabbing once more for the exposed jugular.

He lunged murderously at his mark. Yes, and this time he found it. His teeth had touched the pudgy throat, and began to cleave their remorseless way to the very life of the man who had slain Lady.

But, out of the jumble of cries and stamping feet and explosive shouts from the scared onlookers on the veranda above, one staccato yell pierced the swirl of rage-mists in the avenging collie's brain.

"LAD!" came the Master's sharp, scandalized mandate. "LAD!!!"Hating the thought of desisting from his cherished revenge, the dog heard and heeded. With visible reluctance, he drew back from the slaughter; and turned his noble head to face the man who was running down the steps toward him.

Lad knew well what he might expect, for this thing he had done.

He knew the Law. He knew, almost from birth, the courteous tolerance due to folk among whom his deities took him. And now he had made an industrious effort to kill one of these people.