// #11. The Fairy Draws Greater Loads

Pittsburg has 5,000,000 tons of coal every year that it wishes to send South, much of it as far as New Orleans - 2,050 miles. What force is sufficient for moving such great mountains so far? Any boy may find it.

Tie a stone to the end of a string, whirl it around the finger and feel it pull. How much is the pull? That depends on the weight of the stone, the length of the string, and the swiftness of the whirl. In the case of David's sling it pulled away hard enough to crash into the head of Goliath. Suppose the stone to be as big as the earth (8,000 miles in diameter), the length of the string to be its distance from the sun (92,500,000 miles), and the swiftness of flight the speed of the earth in its orbit (1,000 miles a minute). The pull represents the power of gravitation that holds the earth to the sun.

If we use steel wires instead of gravitation for this purpose, each strong enough to support half a score of people (1,500 pounds), how many would it take? We would need to distribute them over the whole earth: from pole to pole, from side to side, over all the land and sea. Then they would need to be so near together that a mouse could not run around among them.

Here is a measureless power. Can it be gotten to take Pittsburgh coal to New Orleans? Certainly; it was made to serve man. So the coal is put on great flatboats, 36 x 176 feet, a thousand tons to a boat, and gravitation takes the mighty burden down the long toboggan slide of the Ohio and Mississippi Rivers to the journey's end. How easy!



One load sent down was 43,000 tons. The flatboats were lashed together as one solid boat covering six and one half acres, more space than a whole block of houses in a city, with one little steamboat to steer. There is always plenty of power; just belt on for anything you want done. This is only one thing that gravitation does for man on these rivers. And there are many rivers. They serve the savage on his log and the scientist in his palace steamer with equal readiness.

// #11. The Fairy Draws Greater Loads

Pittsburg has 5,000,000 tons of coal every year that it wishes to send South, much of it as far as New Orleans - 2,050 miles. What force is sufficient for moving such great mountains so far? Any boy may find it.

Tie a stone to the end of a string, whirl it around the finger and feel it pull. How much is the pull? That depends on the weight of the stone, the length of the string, and the swiftness of the whirl. In the case of David's sling it pulled away hard enough to crash into the head of Goliath. Suppose the stone to be as big as the earth (8,000 miles in diameter), the length of the string to be its distance from the sun (92,500,000 miles), and the swiftness of flight the speed of the earth in its orbit (1,000 miles a minute). The pull represents the power of gravitation that holds the earth to the sun.

If we use steel wires instead of gravitation for this purpose, each strong enough to support half a score of people (1,500 pounds), how many would it take? We would need to distribute them over the whole earth: from pole to pole, from side to side, over all the land and sea. Then they would need to be so near together that a mouse could not run around among them.

Here is a measureless power. Can it be gotten to take Pittsburgh coal to New Orleans? Certainly; it was made to serve man. So the coal is put on great flatboats, 36 x 176 feet, a thousand tons to a boat, and gravitation takes the mighty burden down the long toboggan slide of the Ohio and Mississippi Rivers to the journey's end. How easy!



One load sent down was 43,000 tons. The flatboats were lashed together as one solid boat covering six and one half acres, more space than a whole block of houses in a city, with one little steamboat to steer. There is always plenty of power; just belt on for anything you want done. This is only one thing that gravitation does for man on these rivers. And there are many rivers. They serve the savage on his log and the scientist in his palace steamer with equal readiness.