Abstract: The present invention relates to a method and apparatus for starting and maintaining a long electrical arc in an arc chamber containing a few atmospheres of pressure of an ionizable gas. An electrical potential difference is maintained between two fixed primary electrodes while a short arc is created between the first primary electrode and a pilot electrode, creating ionized gas. The ionized gas is caused to flow towards the second primary electrode thus creating a region of ionized gas between the two primary electrodes, and hence causing a long arc to be struck. This method does not require relative electrode movement as was the case previously.