Inhabitants of Mammoth Island have decided to make gravel for their new roads by dropping boulders off a tower and smashing them to bits. A young Islander suggests that it would take less effort to roll the boulders up an inclined plane than to hoist them up the side of the tower.
General Note
Animated.
Based on the Dorling Kindersley book / by David Macaulay.
Volume number assigned by cataloger based on publisher numbers.