Mark Twain, the well-known humorist, lectured last evening at Library Hall, under the auspices of the Young Men's Library Association, on the "American Vandal Abroad." He first pitched into the guides who beset and betray American travellers in Europe, then went on to give a ludicrous history of Columbus and an Egyptian mummy, to which he was introduced at Genoa and Rome, respectively. He smoked the narghali in Turkey, inspected the wall where St. Paul was let down in the basket which was sold for firewood, went to the pyramids, where he took dinner or something else, with the resident mummy, and whistled "Auld Lang Syne" on the Rock of Gibraltar. He did not think much of the mummies, but preferred a "fresh corpse." The "Grand Quaker City Holy Land funeral excursion" and the Vandal, a doctor, or "body snatcher," on board, were introduced and warmly received with laughter by the audience. A sailor, who was afflicted with an attack of "horizontal parallax," got from the doctor a recipe of four shovelsful of laudanum four times a day, and a mustard plaster about the size of a saddle, across the small of his back, the laudanum to put him asleep and the blister to waken him up. The vandal was also in Paris looking at the can-can and the accompaniments. The pretense of understanding the French language made by Americans was ably satirized. There were several relic-hunters in the ship. At the Crimea one of them found the jaw bone of a horse, took it aboard the ship, put it among his collection, and labelled it "the jaw bone of a Russian General." At Milan they captured the cathedral and were captivated by a "freshly skinned" man, with whom they exchanged cards. The Vandal also caught trout in Lake Como and then went off the Venice with the fish, where he got a good price for them on the Rialto, and with the proceeds paid for a ride in a gondoller of the neuter gender on the grand canal, from which they got a grand view of the palaces, &c. The young ladies in Venice have their back hair done up in "cruppers," somewhat like the Chicago beauties. The Venetian belles get their shopping sent home in "scows." The hackmen drive their teams in the water. At Padua he broke off the big toe of Romeo and Juliet for a relic, and then went to Bologna to investigate the manufacture of sausages. He put up at Naples, next lit his cigar at the flame of Vesuvius, and breathed the successor to the air of Demosthenes on the Acropolis at Athens or somewhere else. The atmosphere of Greece is as clear as the nose of a man with a cold in his head. The Vandal visited his friend, the Emperor of Russia, took breakfast with his brother; was taken with the premises he occupied, and finally, after inviting the Russian Czar to call upon him at No. 404 Seventh Avenue, San Francisco, took himself off, as he could not bear to prolong the affecting interview. After hoping the houses of the audience would not take fire, he bid them good night, and concluding by saying that, "considering the manner in which juries in Chicago are constituted, I hope there is nothing libelous in anything I have said." [Applause and laughter.] Mr. Twain then retired.

Mark Twain (Samuel G. Clemens), is a gentleman of some notoriety, and his effusions are constantly making the rounds of the press. The following sketch will be interesting to those who have not the pleasure of his acquaintance: Blessed with long legs, he is tall, reaching five feet ten inches in his boots; weight, 167 pounds; body lithe and muscular; head round and well set on considerable neck, and feet of no size within the ken of a shoemaker, so he gets his boots and stockings always made to order. Next to Grant he wears the belt for smoking. He smokes tobacco. Drink never crosses the threshold of his humorous mouth. Fun lurks in the corners of it. The eyes are deep set and twinkle like stars in a dark night. The brow overhangs the eyes, and the head is protected from the weather by dark and curling locks. The face is eminently a good one, a laughing face, beaming with humor and genuine good nature. He looks as if he would make a good husband and a jolly father. As a humorous lecturer, he is a success. There is nothing in his lectures, for he very properly sacrifices everything to make his audience roar, and they do it. His manner is peculiar; he hangs round loose, leaning on the desk, or flirting round the corners of it; then marching and counter-marching in the rear of it, marking off ground by the yard with his tremendous boots. He would laugh at his own jokes, but that his doing so would detract from the fun of his hearers, so he contents himself by refusing to explode, and swallowing his risibility until the lecture is over, when he feels easier, and blows off steam. His voice is a long monotonous drawl, well adapted to his style of speaking. The fun invariably comes in at the end of a sentence, after a pause. When the audience least expects it, some dry remark drops and tickles the ribs, and endangers the waist buttons of the "laughists." During the evening, as if to prove that there was something besides humor in him, he branched out into quite eloquent passages, which were applauded. The lecture was good and the attendance large.