1. See the suggestion on the treatment of the statistics in sect. 315. Combine the statistics of the sections 315 and 342 in one chart, if practicable. See below, sect. 354, for the explanation of carrying power; a steamer is estimated to have four times the efficiency of a sailing vessel, in this table. 2. What is the cost of transportation over roads in your vicinity? What system of construction and maintenance is pursued? 3. Write an essay on one of the following topics, from the circulars of the Office of Road Inquiry, U. S. Department of Agriculture. (Copies may probably be secured gratis on application.) (_a_) The proper method of constructing and repairing earth roads. [Circular no. 8.] (_b_) Methods of constructing macadamized roads. [No. 21.] (_c_) Repair of macadamized roads. [No. 30.] (_d_) The best system of maintaining roads. [No. 24.] (_e_) Systems of State aid. [No. 32, Minn.; No. 35, N. Y.] 4. Effect on the agriculture of the U. S. of the present roads. [Report of the U. S. Industrial Commission, 1900, vol. 10, pp. ccix-ccxvi.] 5. The place of canals in the transportation system of a modern European state. [O. Eltzbacher, The lesson of the German waterways, Contemporary Review, Dec., 1904, 86: 778-797.] 6. Early history of the railroad. [See a biography of Stephenson, by Smiles, or in one of the encyclopedias or biographical dictionaries.] 7. Early locomotives. [Thurston, Hist., chap. 4.] 8. American improvements in locomotives and cars. [Amer. Railway, p. 100 ff.] 9. Improvements in railroad construction. [Same, p. 1 ff.] 10. Feats of railroad construction. [Same, p. 47 ff.; Vernon-Harcourt, chap. 2.] 11. Modern bridges. [Vernon-Harcourt, chaps. 6, 7.] 12. Modern railroad management in the United States. [Amer. Railway, 149 ff.] 13. Development of railroad organization and its effects. [Same, pp. 344-359.] BIBLIOGRAPHY A good article on the history of highways will be found in the Edinburgh Review, 1864, vol. 119, p. 340 ff. See also Smiles’ Lives of the engineers, and, for conditions in England before the railroad, Stanley Harris, Old coaching days, London, 1882, or W. O. Tristram’s book on the same subject, London, 1893. For the bibliography of canals and railroads see Bowker and Iles, and Palgrave’s Dictionary. Among the many books the following will probably be most serviceable: E. J. James, Canal and railway; J. S. Jeans, Water-ways; E. R. Johnson, *Railways; A. T. Hadley, *Railroad transportation. All of these include historical and descriptive matter, along with economic criticism. **The American Railway, made up of articles contributed by various authors to Scribner’s Magazine, has much matter of value and interest to the student of the history of commerce. CHAPTER XXXI MEANS OF NAVIGATION AND COMMUNICATION