Show causes of willo wilio will wili o th ewis ignis fatrus is the name applied to the pale flame also called will othe wisp and jacko jack o lantern sometimes seen flickering over marshy ground and it is said ovar churchyards no entirely satisfactory explanation of the phenomenon has been advanced but it I 1 is s generally believed that the effect is due to the spontaneous ignition of gases especially methane or marsh gas cha produced by the disintegration of dead plant and possibly animal matter |