Make a Simple Siphon

Make a Simple Siphon

You will need: Length of rubber tubing, two large jars.

This is an extremely simple experiment, yet one that often has practical value when it becomes necessary to empty a receptacle of liquid, especially to make it rise over an obstruction.

When you drink lemonade through a straw, you are making the liquid overcome the force of gravity. You first suck all the air from the straw, which allows the outer air to press down upon the surface of the lemonade and assist it in its journey from the glass to your mouth.

With a siphon, you do the same thing-empty a glass of water-or just as easily, a large tank containing many gallons.

To make a siphon, fill an empty jar with clean water and insert one end of the tubing into the jar. Arrange a second jar at a lower level within easy reach of the other end of the tubing.

Suck the free end of the tube until you have removed all the air and the tube is filled with water. Remove the end of the tube carefully from your mouth, holding a finger tightly over the end as your tongue lets go, so that suction is maintained.

Place the end of the tubing in the empty jar and remove your finger from the end. The water will flow steadily now from the top jar into the bottom one for as long as you can keep the top end of the tube below the surface of the water you are emptying.