SUMMARY
1. Between 1840 and 1860 the population increased from 17,000,000 to 31,000,000.
2. During this period millions of immigrants had come.
3. As population continued to move westward new states and territories were formed.
4. In one of these new territories, Utah, were the Mormons who had been driven from Illinois.
5. The rise of a new state on the Pacific coast revived the old demand for a railroad across the plains, and surveys were ordered.
6. East of the Mississippi thousands of miles of railroads were built, and the East, the West, and the far South were connected.
7. This period is marked by many great inventions and discoveries, including the telegraph, the sewing machine, and the reaper.
8. It was in this period that trade relations were begun with China and Japan.
[Illustration: MODERN HARVESTER.]