This iconic scientific lamp was originally created by Nikola Tesla in 1894, following his experiments with high voltage currents. The plasma ball demonstrates the properties of electrical discharges, which you can control with your fingers as you touch the lamp. The globe is a sphere that has most of its air replaced with 3 noble (inert) gases - neon, argon and xenon. A high frequency alternating current electrode is in the center, which discharges and excited filaments the strike inside the globe. When you touch the globe, these filaments are attracted to the spot. This globe runs on AC power and is 20cm in diameter. The perfect geek gift for teens and adults who love science and all things mesmerizing! WARNING: This item is not a toy and should not be placed near sensitive electronic equipment and is not suitable for people with a pacemaker.