"I don't think there's any need of their running out," said Leonard, emphatically. "I agree with Webb in one thing, if I can't follow him in all of his scientific theories--we have both decided never to let a field grow poor, any more than we would permit a horse or cow to so lose in flesh as to be nearly useless; therefore we not only buy fertilizers liberally, but use all the skill and care within our power to increase them. Barn-yard manure can be doubled in bulk and almost doubled in value by composting with the right materials. We make the most of our peat swamps, fallen leaves, and rubbish in general. Enough goes to waste on many farms every year to keep several acres in good heart. But, as you say, we cannot begin to procure enough to go over all the land from which we are taking crops of some kind; therefore we maintain a rotation which is adapted to our various soils, and every now and then plow under a heavy green crop of clover, buckwheat, or rye. A green crop plowed under is my great stand-by." "I plowed under a crop of buckwheat once," said the squire, discontentedly, "and I didn't see much good from it, except that the ground was light and mellow afterward." "That, at least, was a gain," Leonard continued; "but I can tell you why your ground was not much benefited, and perhaps injured. You scarcely plowed under a green crop, for I remember that the grain in your buckwheat straw was partly ripe. It is the forming seed or grain that takes the substance out of land. You should have plowed the buckwheat under just as it was coming into blossom. Up to that time the chief growth had been derived from the air, and there had been very little drain upon the soil." "Well!" exclaimed the squire, incredulously, "I didn't know the air was so nourishing."