A very much larger volcano, Cotopaxi, has, at different times, had most frightful eruptions, but on account of its situation, has not done so much damage as Etna and Vesuvius. Just before an eruption occurs dull roars are heard inside of the mountain, which seems to shake with the action of the lava boiling up within it. Presently columns of smoke shoot up, then sheafs of flame rise into the air with masses of cinders, and burning rocks. And then the lava-streams pour over the sides, and roll down into the plains. Some volcanoes are always smoking when not in active eruption, but the active volcanoes usually take long rests. The people who live on, or near these burning mountains rely upon this fact for safety. But it is not a very safe reliance, for their periods of rest are very irregular; and they may break forth when least expected. The greater number of these mountains throw out flames and lava, but some send out hot mud instead, and others boiling water. There are volcanoes that seem to have burned themselves out, and are said to be extinct. Men can go down into the craters of these, from whence the flames, and lava formerly issued, and examine them. Some of these immense holes, or craters are now filled with forests, and in others there are lakes. Others again are nothing but rocky ravines. Orizaba, in Mexico, is an extinct volcano, with a monstrous crater. Persons standing on the opposite sides of this crater can barely see each other, the distance between them is so great. [Illustration: CRATER OF ORIZABA.] The small volcanoes are more active than the large ones. Little Stromboli is nearly always sending up flames, while the lofty Cotopaxi is quiet sometimes for a century. THE ABSENT-MINDED BOTANIST. The learned Mr. Nathaniel P. Reed, a native of New Jersey, and a man well known to all the botanical and agricultural societies of the civilized world, had, in the course of some thirty years spent in patient and careful investigation into the structure and habits of plants, acquired the power of completely abstracting his mind from all its surroundings while engaged in his favorite pursuit. This was often a very fortunate thing for him. But then, again, sometimes it was very unfortunate. He traveled everywhere, searching for specimens of plants. He never seemed to get tired of this study. Over hot, sandy deserts, and through savage forests he went undaunted; and, if he found a new flower, or tree, he felt he was fully rewarded. At last, he reached Cape Town in Southern Africa, a region he had never before visited. A party of European hunters was just on the point of starting on an expedition into the woods and jungles, and, in an evil hour for them, asked Mr. Reed to join them. He at once accepted the invitation, for it was a fine opportunity to hunt up new plants.