Abstract: A system for separating two immiscible fluids of different densities. An outer conduit extends down from the earth's surface at least to a depth determined as a function of the average difference between the weights of the two fluids to be separated. An inner conduit extends down from the earth's surface inside the outer conduit and terminates above the bottom of the outer conduit so as to be in open communication with the space defined in the outer conduit. A mixture of two immiscible fluids is supplied to one of the conduits and the system is kept under sufficient pressure to maintain a defined fluid separation region within the one conduit such that the lower limit of the fluid separation region, below which occurs substantially only the heavier of the two immiscible fluids, is maintained above the lower end of the inner conduit.

Abstract: A spark plug for internal combustion engines, both two-stroke and four-stroke cycle, in which the insulating core, the central electrode and the conductive metal casing which carries the insulating member and electrode together with the gasket or sealing structure are essentially identical to conventional spark plugs. The projecting portion of the central electrode and the "ground" electrode have a structural and functional relationship different from commercially available plugs. The central electrode projects from the inner end of the metal spark plug casing and the ground electrode, made from a thin flat strip of conventional ground electrode material, has a substantially greater length than that of normal plugs.