=328. Progress less in agriculture than in other branches of production.=—Still, when all is said, agriculture is the branch of production which has been affected least by the changes of the century. The farmer is still bound to the soil and subject to the weather. Steam power has not made for itself the place which sanguine men once thought it would win. In Europe reforms have been effected in sweeping away antiquated institutions affecting the personal liberty and property rights of cultivators, who now, in free association, can work far more efficiently than before. In other continents the extension of the modern transportation system has effected a revolution in the choice of crops and the means of marketing them. Neither transportation, steam power, nor machinery, however, has vitally affected the methods by which crops are grown; and when the first fertility of new land has been exhausted and a growing population clamors for a cheap food supply, the world will find that one of its great problems is still unsolved. =329. Function of machinery.=—For the great changes effected by the use of steam we look, of course, not to agriculture but to manufactures and transportation. These changes have been wrought through the medium of machinery, and the reader is asked to give particular attention now to the part which machinery plays in modern life. I spoke above of coal as offering power to men. How can you apply this power to a useful purpose? First, you must burn the coal under a boiler to produce steam; second, you must translate the expansive power of steam into regular forceful motion in an engine; finally, you must apply the force and the motion in just the way that is wanted by means of a machine. Evidently machinery does not depend altogether upon steam. Rude machines, mills for grinding grain, for example, were run by wind or water power long before the steam-engine was invented; water power is being transmitted by electricity in increasing quantities at present; and men hope that we shall be able to use the heat of the sun or the force of the tides to run machinery in the future.