Sir,--I have read several letters in the papers complaining of the fog, and asking not only how one is to protect the system from its injurious effects, but also soliciting information as to how one is to safeguard oneself against street accident, if obliged to quit the premises during its prevalence. The first is simple enough. Get a complete diver's suit, put it on, and let an attendant follow you with a pumping apparatus, for the purpose of supplying you with the fumes of hydro-bi-carbon (DAFFY's solution) in a state of suspension. This will considerably assist the breathing. To avoid street accident, wear an electric (SWANN) light, five hundred candle power, on the top of your hat, round the brim of which, in case of accident, you have arranged a dozen lighted night-lights. Strap a Duplex Reflector on to your back, and fasten a Hansom cab-lamp on to each knee. Let a couple of boys, bearing flaming links, and beating dinner-gongs, clear the way for you, while you yourself shout "_Here comes the Bogie Man!_" or any other appropriate ditty, through a fog-horn, which you carry in one hand, while you spring a policeman's ancient rattle vigorously with the other. You will, if thus provided, get along capitally. Be careful at crossings, for your sudden appearance might possibly frighten an omnibus horse or two, and cause trouble. I haven't tried all this _yet_ myself, but a friend of mine at Colney Hatch assures me he has, and found it a great success. As I think, therefore, it may prove a boon to your numerous readers, I place it at your disposal with much pleasure, and have the honour to be, Sir, Your obedient servant, A CAUTIOUS CARD. * * * * * [Illustration: "KEEP THE POT A-BOILING!"] * * * * * [Blank Page] THE CHRISTMAS COLLEGE FAIRY. CHAPTER I.--_THE STRANGE VISITOR._ On the evening of the 24th of December, 1874, the Senior Dean of St. Michael's, the Reverend HENRY BURROWES, was sitting in his comfortable rooms in the Great Court. He had, for reasons of his own, decided to spend the Christmas Vacation in Cambridge. His bed-maker, Mrs. JOGGINS, had entered a mild protest, but it been unavailing. Mr. BURROWES was a man of forbidding aspect and of unbending character. During the five years that he had held his office, he had enforced discipline at the point of the bayonet, as it were, and he boasted with pardonable pride that he had broken the spirit of the haughtiest and least tractable of the Undergraduates. Everybody had been gated at eight o'clock. Many had been sent down. Tears and denunciations were alike unavailing. The ruthless Dean had pursued his course without flinching. A very mild reading-man had attempted his life by dropping a Liddell and Scott on to his head from a first-floor room. This abandoned youth had been screened by his comrades, and had ultimately escaped in spite of the efforts of the justly incensed Dean. [Illustration]