Mr. Kesselbach stopped short on the threshold of the sitting&ndash;room, took his secretary&#39;s arm and, in an anxious voice, whispered:<br />&quot;Chapman, some one has been here again.&quot;<br />&quot;Surely not, sir,&quot; protested the secretary. &quot;You have just opened the hall&ndash;door yourself; and the key never left your pocket while we were lunching in the restaurant.&quot;<br />&quot;Chapman, some one has been here again,&quot; Mr. Kesselbach repeated. He pointed to a traveling&ndash;bag on the mantelpiece. &quot;Look, I can prove it. That bag was shut. It is now open.&quot;<br />Chapman protested.<br />&quot;Are you quite sure that you shut it, sir? Besides, the bag contains nothing but odds and ends of no value, articles of dress. . . .&quot;