Fire Engines
The fire engine is basically a big water-pumping machine on wheels. A typical engine has a built-in 1,000 gallon water tank. It can suck in water through hoses, either from a hydrant or a pond or lake. Inside, it has a spinning impeller (like a spiral-shaped propeller), driven by a diesel engine. When water comes into the pump, the spinning impeller slings it outward. This pressurizes the water so that it will flow rapidly through any connected hoses.

The pump operator moves a series of levers and switches on the pump panel. They direct the water to the different hoses at different pressures. For a super-strong stream of water, firefighters can use the deluge cannon on top of the engine. A typical gun can blast 1,000 gallons of water per minute.

A typical engine also carries about 20 gallons of foam, which firefighters use to extinguish chemical fires (water may spread the chemical, making the fire worse).

Fire engines act as personnel carriers (firefighters ride in them). They also have dozens of compartments with all kinds of tools, including medical equipment, 10-foot pikes poles for pulling down walls, wrenches for connecting hoses to hydrants and turning hydrants on, the "Jaws of Life" machine for freeing people stuck in wrecked cars, tarps for protecting furniture from water, sledgehammers, bolt cutters and even chain saws.