Bat looked at Nora; in the semi-dark of the car her face was drawn and despairing. There was not a ray of hope in Scanlon's own breast, and patiently he listened as the quiet voice of the investigator went on:
"The by-play between the young man and the girl, during their examination by Dr. Shower, which you reported so graphically to me, took my attention. He must have seen suspicion heading his way, and yet he took no real steps to prevent it. And then there was something else. You reported that he had appeared in the sitting-room after you had gone there with Osborne and Dr. Shower to examine the body; and his anxiety then concerning the nature of the instrument used in the commission of the crime struck me as being a bit unusual. He seemed to dread, apparently, that this would be shown to be something caught up on the spur of the moment, something belonging in the room. Without putting it in so many words, he seemed to insinuate that a regulation weapon, such as might have been brought into the house by an unknown, had been used. In this I seemed to detect not only a desire to throw the police off the track, but also the existence of an element of hope. In the back of his mind was the thought that, after all, his sister might not be guilty. If the weapon used was not one that had been ready to her hand, there was a chance that she was innocent.
"However, the finding of the candlestick must have dissipated this hope, and when they charged him with the crime, he merely denied it; he, I think, feared to do or say anything which might direct the attention of the police definitely away from himself; for, in doing this, they might chance to think of his sister."
"But," said Nora, "you have no proof that all of this is true."
"Not proof," said Ashton-Kirk, smiling. "But there are certain almost unmistakable indications. One of these I brought about by my confidence to the police regarding the possibility of a woman being connected with the case. I felt that if he believed his sister guilty that this would stir him to some further action. It did, as you know. He instantly canceled his denials, and admitted the crime."
"Tell me," said Scanlon, "haven't you ever thought that maybe some one else had done this thing? Has your mind always been fixed on these two? For example, didn't you, also, once think Miss Cavanaugh had a part in it?"
"Not for a moment," smiled Ashton-Kirk.
"Not even when I told you how I'd seen her at Bohlmier's?"
"Not even then. Of course I didn't know the explanation of that, and at once set about finding one. Fuller was put to work looking up Bohlmier, and in one day had his record complete. The man is a skilful blackmailer; he has practiced in many cities and has served more than one term in jail. I knew at once what had occurred; the two men fancied they 'had something on' Miss Cavanaugh regarding this murder, and had endeavored to extort money from her. I leave it to you," with a smiling nod toward Nora, "to tell how near I am to the facts."
The girl made a low-voiced, unintelligible reply, and then they ran on for some distance in silence. Suddenly Ashton-Kirk signaled the driver and the car came to a stand; the investigator pointed to some buildings at no great distance; a locomotive with a few cars trailing behind it was panting laboriously away from these, its headlight glaring morosely into the darkness.