Tonight it was ascertained that a young man named Flaherty had escaped from the prison. He was Hunter's roommate and, singular to say, his father had had him incarcerated to prevent his joining the Southern Army! I failed to state in my record of yesterday that Miss Belle Boyd left for Virginia with the exchange of prisoners and that, on the night previous, the prison guard having been changed, Flaherty and Hunter and I went down stairs and completely fooled the greenhorn who stood her sentinal. I learned from her her own life history. It was quite interesting, but too long to narrate here. Indeed, it was near one o'clock when she finished. She was quite an important character in the prison. The illustration of her conduct during one evening which I have previously given in these pages is a fair sample of her general demeanor whilst here. The immediate cause of her arrest was her being detected bearing dispatches to Gen Jackson in the valley of Virginia.