Next to the destruction of trees in clearing operations came the use of wood for fuel. A river steamboat or railroad locomotive required from twenty to thirty cords per day. “Woodhawks” literally denuded whole forests to supply these needs. Houses were largely built of wood, and it was liberally used in all domestic operations. In winter the family kept warm, not by securing “sich uppish notions” as blankets, but by throwing more wood on the fire, “nobody needn’t suffer with a great fire to sleep by.”[262] Rails were used in building fences at the rate of twenty-six thousand per section. The increase of population and acceleration of industrial activity in the early nineteenth century took a heavy toll from the forests. Fires were started by sparks from steam engines and by careless hunters, with the result that the precious blotter of humus, millenniums in building, was often destroyed in a flash. For two centuries America had advanced westward in a wood age, and trees were always in the way. However, there were wise men who had always deplored tree waste. William Penn insisted that one acre of forest remain for each five cleared. Benjamin Franklin invented a stove to save fuel. George Washington and Peter Kalm warned of dangers ahead from floods and erosion through wanton clearing of land.[263] In 1813, Thomas Jefferson sagely wrote: The spontaneous energies of the earth are a gift of nature, but they require the labor of man to direct their operation. And the question is so to husband this labor as to turn the greatest quantity of this useful action of the earth to his benefit.[264] It will be noted that the foregoing suggestions were made by practical men upon sound considerations. However, there came an occasional complaint upon the philosophic and aesthetic level. Jonathan Edwards, André Michaux, George Catlin, and William Cullen Bryant were among those who visualized nature as a dynamic organization of living creatures worthy of existence in their own right and for the joy they gave. Their appreciation is illustrated by this verse: To see a World in a Grain of Sand And Heaven in a Wild Flower, Hold Infinity in the palm of his hand, And Eternity in an hour. To be sure, little resulted from this approach; the time was not ripe. But these slender stirrings of thought and twitchings of conscience in high places were bound to be fruitful in results later on.