14. Power. (Smith, Commerce and Industry, chapter ix.)
15. Mineral industries in the United States. (Bishop and Keller, Industry and Trade, part iv. Smith, Commerce and Industry, chapters viii, xiii, xiv, and xv.)
16. Manufacturing industries in the United States. (Bishop and Keller, Industry and Trade, part v.)
17. Trade routes of North America. (Smith, Commerce and Industry,
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