could really only be held by development of such defence, and the ingenuity of the students in organizing new systems of attack had to be met by improvement in their repulse. It was armour-plating _versus_ guns, and the armour-plating generally saved the ship. Professor Letts would have been a lost man one morning at the chemistry lecture had he not caught the man who threw the lighted squib on the lecture table, where it fizzed and bobbed amongst his neatly fixed-up apparatus for an hour with the gases. “You, sir!” he cried, in his determined, assertive manner that always commanded and secured respect; “you, sir, you squib-thrower, come forward to the black-board! You are going up for your preliminary science; give me the chemical formula for that explosive. We are considering nitrogen this morning; you shall give the audience the benefit of your, doubtless, complete knowledge of your favourite gas. Nitrogen _is_ your favourite gas, is it not, Mr. Albery?” Now poor Albery had to maintain a reputation for chemistry on a very slender basis, and withal was a nervous man; and being all the while unmercifully twitted by Mr. Letts, his symbols got mixed, and he returned to his seat feeling that the squib itself was not more completely “bust up” than he. One of the best retorts was made by the professor of anatomy, who, entering the theatre for lecture one afternoon, found that the skeleton, which always hung on a stand near the lecturer’s table, had been removed from its frame and placed on one of the benches in the auditorium, and was seated in a free and easy manner, with a long clay pipe in its ghastly jaws, and a pewter pot in its left hand. Dr. Hawkes took in the situation at a glance, and said, “Gentlemen, I miss our old friend the skeleton from its accustomed place, and perceive it in a new character seated amongst you. We shall, this afternoon, go on with our remarks on the vertebral column, and I have no doubt my address will be as useful to its empty cranium as it will be to those by which it is surrounded.” It was many a long day before that trick was played again.