It was eleven o\'clock in the morning, and Mr. Charles Yeldham was hard at work, his oak rigidly closed, the sleeves of his dressing-gown turned up, his hair in a grand state of "towzle," caused by the frequent passage of his hands through it; a shower of fresh ink-splotches dotting the carpet close by his desk, and other indubitable signs of a hard case of "treadmill." It had occurred to Mr. Yeldham, in the midst of applying a wise saw to a modern instance, that somebody was tapping at his outer door; but entirely engrossed by the v............