From documents on the person of one of these young Britishers, it appeared that General Clarke was in command of a brigade behind the lines which Jack had been watching and robbing. When Jack delivered his report the Chief called him a brave lad and said: "It is valuable information you have brought to me. Do not speak of it. Let me warn you. Captain, that from now on they will try to trap you. Perhaps, even, you may look for daring enterprises on that part of their line." The General was right. The young scout ran into a most daring and successful British enterprise on the twentieth of January. The snow had been swept away in a warm rain and the ground had frozen bare, or it would not have been possible. Jack had got to a strip of woods in a lonely bit of country near the British lines and was climbing a tall tree to take observations when he saw a movement on the ground beneath him. He stopped and quickly discovered that the tree was surrounded by British soldiers. One of them, who stood with a raised rifle, called to him: "Irons, I will trouble you to drop your pistols and come down at once." Jack saw that he had run into an ambush. He dropped his pistols and came down. He had disregarded the warning of the General. He should have been looking out for an ambush. A squad of five men stood about him with rifles in hand. Among them was Lionel Clarke, his right sleeve empty. "We've got you at last--you damned rebel!" said Clarke. "I suppose you need some one to swear at," Jack answered. "And to shoot at," Clarke suggested. "I thought that you would not care for another match with me," the young scout remarked as they began to move away. "Hereafter you will be treated like a rebel and not like a gentleman," Clarke answered. "What do you mean?" "I mean that you will be standing, blindfolded against a wall." "That kind of a threat doesn't scare me," Jack answered. "We have too many of your men in our hands." CHAPTER XV IN BOSTON JAIL Jack was marched under a guard into the streets of Boston. Church bells were ringing. It was Sunday morning. Young Clarke came with the guard beyond the city limits. They had seemed to be very careless in the control of their prisoner. They gave him every chance to make a break for liberty. Jack was not fooled. "I see that you want to get rid of me," said Jack to the young officer. "You'd like to have me run a race with your bullets. That is base ingratitude. I was careful of you when we met and you do not seem to know it." "I know how well you can shoot," Clarke answered. "But you do not know how well I can shoot." "And when I learn, I want to have a fair chance for my life." Beyond the city limits young Clarke, who was then a captain, left them, and Jack proceeded with the others.