Editing Fusor (section)

===Design===
Farnsworth's original fusor designs were based on cylindrical arrangements of electrodes, like the original multipactors. Fuel was ionized and then fired from small accelerators through holes in the outer (physical) electrodes. Once through the hole they were accelerated towards the inner reaction area at high velocity. Electrostatic pressure from the positively charged electrodes would keep the fuel as a whole off the walls of the chamber, and impacts from new ions would keep the hottest plasma in the center. He referred to this as [[inertial electrostatic confinement]], a term that continues to be used to this day. The voltage between the electrodes needs to be at least 25 kV for fusion to occur.