heard him speak, as the car moved gently away from him.'
Marlowe rose from his chair and pressed his hands to his eyes. He was flushed with the excitement of his own narrative, and there was in his look a horror of recollection that held both the listeners silent. He shook himself with a movement like a dog's, and then, his hands behind him, stood erect before the fire as he continued his tale.
'I expect you both know what the back-reflector of a motor car is.'
Trent nodded quickly, his face alive with anticipation; but Mr. Cupples, who cherished a mild but obstinate prejudice against motor cars, readily confessed to ignorance.
'It is a small round or more often rectangular mirror,' Marlowe explained, 'rigged out from the right side of the screen in front of the driver, and adjusted in such a way that he can see, without turning round, if anything is coming up behind to pass him. It is quite an ordinary appliance, and there was one on this car. As the car moved on, and Manderson ceased speaking behind me, I saw in that mirror a thing that I wish I could forget.'
