On the mantelpiece stood a clock which then pointed to the hour of nine-thirty. It ticked on solemnly, dutifully, wholly indifferent to any wonder save the great and perpetual miracle of Time itself. Minute by minute the long and the short hands crept over the dial, and on the vast looms of Eternity thread by thread was added to the universal fabric of the Past.

Ten-twenty-five, and Martin, out marketing among the stalls in the Reading Terminal Market, was very cheerful over some exceptionally large, juicy oranges. Mr. Trenmore liked oranges. He added two dozen of the fruit to his order and started homeward.

Back there in the library the Cerberus still gleamed where Drayton had flung it down. The Dust still lay on its newspaper, whose matter-of-factness seemed to deride all mystery connected with divorce, murder, or the wonderful cheapness of lace blouses and lingerie at Isaac Fineheimer's Stock Clearance Sale.

And as Martin, on his return journey, crossed Juniper Street, five blocks away, a caller arrived at a certain house on Walnut Street.

He was a short, rotund young gentleman. Attired in a suit of dark green, neatly matched by socks, tie, and the ribbon on his wellblocked hat, the one false note in his color scheme was struck by a pair of bright, too-bright tan shoes.

Twice he had passed the house saunteringly; then boldly ascended Mr. Burford's sedate white marble doorsteps. Boldly indeed he walked up and in at the open door; but once inside his demeanor underwent a change. No cat could have slunk more softly through vestibule and hall; no hunting animal could have been more keenly alert for any sound within the quiet, empty house.

He made straight for the stairs; but with one foot on the first step he paused. Through a half-open door he could see part of a large, book-lined room. Was it empty?

After short hesitation the rotund green gentleman stole over and peered cautiously round the edge of that door!

An instant later, and he had darted across the library with a silent, amazing celerity of movement. His attention, it seemed, had been caught by the Cerberus' gleaming in the sunlight. Picking up the vial, he examined it with swift care, thrust it in his pocket, and turned to leave. His cherubic face now wore the look of one who has achieved good fortune with almost suspicious ease; his pleased smile was half doubtful, and as he moved softly toward the door his small, darting eyes glanced from side to side quickly, thoughtful of hidden danger.

Unluckily for him, however, the real danger in that room was not bidden. It lay in full sight on a newspaper, flat on the floor between two chairs that faced one another companionably.