"Ah, so she could. She must have forgotten us. How could she, after all that has passed!" "Let us hope for the best, let us hope for the best," the doctor would say soothingly. Yet it must be confessed that he was considerably staggered by the turn which things had taken. He had seen so much of the world in his professional capacity that he had become a very reliable judge of character. All his instincts told him that Kate Harston was a true-hearted and well-principled girl. It was not in her nature to leave London and never to send a single line to her friends to tell them where or why she had gone. There must, he was sure, be some good reason for her silence, and this reason resolved itself into one or two things--either she was ill and unable to hold a pen, or she had lost her freedom and was restrained from writing to them. The last supposition seemed to the doctor to be the more serious of the two. Had he known the instability of the Girdlestone firm, and the necessity they were under of getting ready money, he would at once have held the key to the enigma. He had no idea of that, but in spite of his ignorance he was deeply distrustful of both father and son. He knew and had often deplored the clause in John Harston's will by which the ward's money reverted to the guardian. Forty thousand pounds were a bait which might tempt even a wealthy man into crooked paths. It was Saturday--the third Saturday since Girdlestone and his ward had disappeared. Dimsdale had fully made up his mind that, go where he would, Ezra should not escape him this time. On two consecutive Saturdays the young merchant had managed to get away from him, and had been absent each time until the Monday morning. Tom knew, and the thought was a bitter one, that these days were spent in some unknown retreat in the company of Kate and of her guardian. This time at least he should not get away without revealing his destination. The two young men remained in the office until two o'clock. Then Ezra put on his hat and overcoat, buttoning it up close, for the weather was bitterly cold. Tom at once picked up his wide-awake and followed him out into Fenchurch Street, so close to his heels that the swinging door had not shut on the one before the other passed through. Ezra glanced round at him when he heard the footsteps, and gave a snarl like an angry dog. There was no longer any pretence of civility between the two, and whenever their eyes met it was only to exchange glances of hatred and defiance. A hansom was passing down the street, and Ezra, with a few muttered words to the driver, sprang in. Fortunately another had just discharged its fare, and was still waiting by the curb. Tom ran up to it. "Keep that red cab in sight," he said. "Whatever you do, don't let it get away from you." The driver, who was a man of few words, nodded and whipped up his horse.