[TO BE CONTINUED] COLORADO AND THE SOUTH PARK. On the 15th of August, 1871, two brothers and a sister--Sepia, an artist, Levell, an engineer, and Scribe, who is the narrator--left Chicago by the North-western Railroad, bound for Denver in Colorado, about eleven hundred miles west. The first day we were climbing the gradual ascent from the Lakes to the Mississippi, which we crossed at 4.30 P.M., at Clinton. The thirty years which had elapsed since I first traversed this region had changed it from wild, unbroken prairie to a well-cultivated country, full of corn-fields, cattle and flourishing towns. Then I traveled in a wagon four miles an hour, and had to find my own meat in the shape of a deer from the grove, a grouse from the prairie or a duck from the river. Now we rushed across the State in six hours, stopping fifteen minutes for dinner in a fine brick hotel, metropolitan in charges, if not in fare. In 1840, when we arrived at the great river, we waited two or three hours for the ferry-boat, and finally had to cross in a "dug-out," which seemed but a frail vessel to stem the rapid currents and whirling eddies of the Mississippi. Now we crossed upon a railroad bridge of iron, which cost more money than all Iowa contained in 1840. Still, I fancy that the first method of traveling was the more interesting. Through the still summer afternoon we rushed on over the rolling prairies of Iowa, dotted with towns and villages and covered with great corn- and wheat-farms. Here in 1840 was absolute wilderness: we made our hunting-camp seventy-five miles west of the river, and we were twenty miles away from any white settler. Wolves howled and panthers screamed around our camp, we lived upon elk and deer meat, and our only visitors in two weeks were some Sac and Fox Indians, who disapproved of our intrusion upon their hunting-grounds. At 9 A.M. on the 16th we arrived at Council Bluffs, and crossed the turbid and furious Missouri in a steam ferry-boat to Omaha in Nebraska. For many years Council Bluffs was one of the remotest military posts: to go there was to be banished from the world. Now it is a town of ten thousand inhabitants, struggling to overtake its rival on the other bank, Omaha, which has sixteen thousand.