The Fuel Products 127 work of pipe lines. Through these, by means of pumping stations, the oil is forced from the.tank at the source of production to the re- finery near the market (Fig. 104). OUESTIONS, EXERCISES, AND PROBLEMS A. Where the world’s coal is mined. 1. What are the two great coal-producing regions of the world? (Fig. 99.) 2. Make a list of the five countries that produce most coal. beginning with the chief producer. China is thought to stand third among the world’s coal fields. How do you explain her small coal production? What relation has this to political conditions? What two possible explanations can you give for the absence of coal min- ing in equatorial regions? Pennsylvania and England are of about the same size, and each produces more than two hundred million tons of coal annually. What advantages for coal production does each possess ? How coal is formed. From a local coal dealer secure samples of the following kinds of coal : anthracite, bituminous, cannel, and lignite. If possible, get also a piece of peat. This may be found in almost any marsh. In an encyclopedia or a general geography read about the formation, distribution, and uses of the different kinds of coal. Take notes and make a report to the class, using the samples you have gathered to il- lustrate your points. How coal is used. About six tons of coal are burned in the United States each year for every man, woman, and child in the country. Under the following headings, make lists of things that you use, to show in a general way how your share is consumed. (a) Buildings heated by coal. (b) Metals smelted with coal. (¢) Manufactured goods made with machines driven by power obtained from coal. (d) Means of transportation for which the power is furnished by coal. How we may conserve our coal supply. Since coal is exceedingly important and our supply is limited, it is short- sighted to waste it thoughtlessly. It is estimated that for every ton of coal that we burn another has been wasted. Smoke consists of particles of unconsumed coal. In the United States at least twenty million tons of coal pass into the air yearly as soot in smoke. In what other ways is smoke a detriment? Is it a sign of progress that certain cities are fa- mous for their smoke? What are the laws in your city in regard to the smoke nuisance? Consult some encyclopedia to find out the uses of soot.