How To: Build a Leyden jar and use a capacitor

Simple yet effective, capacitors come in a dizzying array of forms and materials, vital to so many circuits for storage, timing, and filtration - the mighty capacitor!

In this installment of the MAKE presents series, Collin Cunningham explains - how to build a Leyden jar, how the capacitor was invented, and how to use one to light an LED.

To make your own Leyden jar, you'll need a plastic film canister (or pill bottle), some glue paste (or tape), basic copper wire, and some aluminum foil. After building a Leyden jar, you'll also learn how to power an LED with a capacitor, charging the capacitor with a 9-volt battery. The charge doesn't last long, but it shows you exactly what a capacitor is for.