Machines that move water

This lesson asks you to describe different ways an object can move, to identify the basic kinds of simple machine, and to describe how they are used in daily life to make tasks easier. The museum links two water machines that show a lever and a wheel and axle; your class will find the other simple machines. ¹

Watch a machine or a toy. Describe each movement you see, for example turning, going back and forth, or going up and down.

Compare what you see with the list of simple machines in the expectation. Say which ones appear, and how each makes the task easier.

Al-Jazari first tells you what a visitor would see: a pool, a pillar, a cow, a wheel and coloured jars ². The cow seems to go round and turn the lifter, but it is hollow wood, carried by a lever with its hooves clear of the platform. Water drives the machine ³. In a room under the floor, water passes over a wheel, and the movement goes upward ³. The shaft turns the cow, not the reverse ².

The cow looks as if it turns the lifter, but the shaft turns the cow. Think of a toy or a machine that moves. How could you find out what really makes it move, and why is looking at the outside not enough?

• The hidden-drive water lifter: a pool whose cow is carried round while jars lift water.
• The double-piston pump: water turns a wheel and gears, and the piston rods move back and forth.
• Al-Jazari: the engineer who described both machines.

Read the cards on the hidden-drive water lifter and on the double-piston pump. Draw each machine and label every part that turns, every part that goes back and forth, and every lever.