"You know no reason at all why you should be brought here?"
"No," the Chinaman answered calmly again, while the light moved about six inches. Trant waited till it returned to its normal position in the center of the screen.
"Do you know an American named Paul Tobin, Wong Bo?"
"No," the Chinaman answered. This time the light remained stationary.
"Nor one named Ralph Murray?"
"No." Still the light stayed stationary.
"Hugh Larkin, Wong Bo?"
"No." Calmly again, and with the light quiet in the center of the screen.
"Walter Newberry?" the psychologist asked in precisely the same tone as he had put the preceding question.
"No," the Chinaman answered laconically again; but before he answered and almost before the name was off Trant's lips, the light—which had stayed almost still at the recital of the other names—jumped quickly to one side across the screen, crossed the first division line and moved on toward the second and stayed there. It had moved over a foot! But the face of the Oriental was as quiet, patient, and impassive as before. The psychologist made no comment; but waited for the light slowly to return to its normal position. Then he took up his pile of portrait photographs.
"You say you do not know any of these men,
