4. Divide the perpendicular on the right-hand side of your chart into spaces, indicating the shares of the chief countries in commerce.
5. Make out a list of three changes coming under each one of the three heads discussed. Example: technical progress, wireless telegraphy; business organization, trusts; political, international arbitration, reciprocity.
6. Early history of the coal trade. [R. L. Galloway, The rise of the coal trade, Contemporary Review, 1892, 62: 569-578.]
7. Industrial and commercial importance of coal. [Edward Atkinson, Coal is king, Century Magazine, 1897-98, 55: 828-830.]
8. Effect of a stoppage of the coal supply. [Stephen Jeans, The coal crisis and the paralysis of British industry, Nineteenth Century, 1893, 34: 791-801.]
9. How does the increase in steam horse-power compare with the increase in the output of coal? With the growth of commerce?
10. Earliest history of the steam-engine (to about 1700). [Thurston, chap. 1, sect. 1.]
11. Earliest applications of the steam-engine. [Thurston, chap. 1, sect. 2.]
12. Development of the engine before Watt. [Thurston, chap. 2.]
13. Development by Watt and his contemporaries. [Thurston, chap. 3.]