Aug. 30.] THE NEW ZEALAND GAZETTE. 1655

resistance by reason of the heated condition of such resistance. (5.) A modification of the process described in the preceding claim which consists in rupturing the heater circuit through the medium of magnetic effects produced within a sealed chamber containing the ballast resistance. (6.) A circuit-controlling device for the heaters of Nernst lamps consisting of a conductor adapted to be connected in series with the glower of the lamp, contact points normally held together by the tension of the said conductor when cold, and means for separating said contact points upon the expansion of the said conductor. (7.) The combination of an electric-lamp glower, a ballast wire of iron in series therewith, a heater circuit in shunt around the glower, and a circuit making and breaking device for the heater circuit, operated by the expansion and contraction of the ballast wire. (8.) The combination of a glower of the Nernst type, an electric heater therefor, a controller for determining the position of the heater, located in a shunt circuit around the glower or in series therewith, means for closing said circuit when the glower is in operation and opening the said circuit when the glower is not in operation. (9.) The combination with a glower of the Nernst type, an electric heater therefor, and a ballast conductor in series with the glower, of an automatic controlling-device for the said heater, located in a shunt to the heater or in series therewith. (10.) The combination with a glower, of a ballast conductor in series therewith, a heating conductor for imparting the initial temperature to the glower, and a cut-out for the heater, operated by the expansion and contraction of the ballast conductor. (11.) The combination with a glower of the Nernst type, an electric heater for the glower, and a controller for determining the relative positions of the heater and glower, the said controller being located in a circuit that is in shunt to the heater and outside the glower circuit. (12.) The combination with a glower of the Nernst type, an electric heater therefor, and a ballast conductor in series with the glower, of an automatic controlling-device for the said heater, located in a shunt thereto or in series therewith. (13.) An electric lamp of the Nernst type, consisting of a glower, a steadying resistance therefor inclosed in an inert gas, a heater, and a controlling-device therefor, having its contacts in an inert gas. (14.) An electric lamp of the Nernst class, comprising a heater, a glower, and a steadying resistance for the glower, and a controller for the heater circuit, having separable contacts, the relative positions of which are controlled by energy derived from the steadying resistance, and a sealed chamber in which said contacts are located. (15.) An electric lamp of the Nernst class, comprising a glower, a ballast therefor located in a sealed chamber, a heater, and a controlling-device therefor, having its contacts within the said sealed chamber. (16.) The combination, in a Nernst lamp, of a steadying resistance for the glower, and a thermostatic cut-out for the heater, both enclosed within a single chamber containing an inert gas. (17.) A cut-out for the heater circuit of lamps of the Nernst class, having its solid metallic contact elements enclosed in an atmosphere of hydrogen. (18.) A cut-out for the heater circuit of Nernst lamps, substantially as shown and described.

(Specification, 9s. 6d.; drawings, 16s.)

No. 12908.—23rd August, 1900.—ALEXANDER JAY WURTS, of Pittsburgh, Pennsylvania, United States of America, Electrical Engineer. Improvements in systems of lighting by Nernst lamps.

Claims.—(1.) The process of operating electric-lighting systems in which glowcrs of the Nernst type are employed which consists in arranging a number of heaters in a single circuit in proximity to the glowcrs, and controlling the operation of the heaters by means of a single device. (2.) In the process characterized in the first claim, controlling the selection of the lamps or groups of lamps to be lighted by separate devices. (3.) A modification of the process characterized in the first claim which consists in combining in the same system lamps or groups of lamps which are under unitary control with lamps provided with separate selecting-devices for each lamp or group of lamps. (4.) In a system of distribution for lamps of the Nernst type, a source of current and a plurality of lamps, the glowcrs of which are connected in parallel and the heaters of which are connected in series to said source, in combination with a manually operated switch in the conductor supplying said heaters. (5.) In a system of distribution for electric lamps of the Nernst type, a source of current and a plurality of lamps, the glowcrs of which are connected in parallel and the heaters of which are connected in series to said source, in combination with a manually operated switch in the conductor supplying said heaters, a switch in each glower circuit, and means for simultaneously actuating said glower circuits by successive closing movements of the heater-circuit switch. (6.) A system of electric distribution for electric lamps of the Nernst type comprising a source of current, a plurality of lamps supplied in parallel from said source and severally provided with means for cutting the same into and out of circuit, a plurality of lamps having glowcrs connected in parallel to the source, and heaters connected in series, and controlling switches for the glower circuits which are actuated simultaneously from the heater circuit. (7.) In an igniting system for Nernst lamps, a generator of electricity, and mains proceeding therefrom, two or more lamps connected up between the mains, and individual circuit-controllers for each lamp, in combination with heaters for the said lamps, and a heater circuit common to all the heaters and controlled by a separate circuit-controller. (8.) A number of Nernst lamps connected up between the mains of an electric-lighting system, a number of heaters arranged in series in proximity to the said lamps, a circuit-controller for each lamp circuit, and a circuit-controller for the heater circuit, the said heater circuit being supplied by any suitable source of current. (9.) In an igniting system for Nernst lamps, a lighting circuit including a number of lamps or glowcrs, an independent heating circuit, containing as many heaters as there are lamps, and a switch controlling the said heater circuit. (10.) In an igniting or lighting system for lamps wherein the glowcrs are brought to a state of conductivity by electrical heating-devices, a number of such lamps arranged in one or more groups at local stations, a corresponding number of heaters in proximity to the said lamps and arranged in series with each other, and a switch controlling the heater circuit, the said switch being located at a central station. (11.) In an igniting or lighting system for that class of lamps in which glowcrs of rare earths are brought to a state of conductivity by electrical heating-devices, a suitable source of current, and mains extending therefrom, a number of lamps connected with the mains and arranged in one or more groups at a local station or stations, a third wire constituting a branch from one of the mains, and a number of heaters corresponding to the number of lamps arranged in similar groups between the said third wire and the other main, and a switch controlling the passage of the current in the said third wire. (12.) In an igniting or lighting system for that class of lamps in which glowcrs of rare earth or mixtures of rare earths are brought to a state of conductivity by electrical heating-devices, a pair of mains and a number of lamps arranged in one or more groups at a local station or stations, a third wire constituting a branch from one of the mains, and heaters connected up between the said third wire and the other main, in combination with a switch and an adjustable resistance in the said heater circuit, the said switch and resistance being located at a central station. (13.) In an igniting or lighting system for that class of lamps in which glowcrs of rare earth or mixtures of rare earths are brought to a state of conductivity by electrical heating-devices, a pair of mains and a number of lamps arranged in one or more groups at a local station or stations, a third wire constituting a branch from one of the mains, and heaters connected up between the said third wire and the other main, in combination with a switch, an ammeter and an adjustable resistance in the said heater circuit, the said switch, ammeter, and resistance being located at a central station. (14.) In an igniting or lighting system for that class of lamps in which glowcrs of rare earth or mixtures of rare earths are brought to a state of conductivity by electrical heating-devices, a generator, a pair of mains extending therefrom, a third wire extending from one side of the generator, and a number of heaters included between said third wire and the opposite main. (15.) In an igniting or lighting system for that class of lamps in which glowcrs of rare earth or mixtures of rare earths are brought to a state of conductivity by electrical heating-devices, a generator and a pair of mains, a derived circuit including heating-devices in series at local stations, and a switch at a central station controlling the derived circuit. (16.) A system of electric lighting by means of Nernst lamps, substantially as shown and described.

(Specification, 10s.; drawings, 8s.)

No. 12909.—23rd August, 1900.—ALEXANDER JAY WURTS, HENRY NOEL POTTER, and MARSHALL WILFRED HANKS, of Pittsburgh, Pennsylvania, United States of America, Electrical Engineers. Improvements in starting-apparatus and cut-outs for Nernst lamps.

Claims.—(1.) The process of operating automatic cut-outs for Nernst lamp heaters which consists in utilising for the operation of such cut-outs the energy of the heater circuit increased by a comparatively small portion of the energy in the glower circuit. (2.) The process of automatically cutting out Nernst lamp heaters which consists in causing the cut-out to rupture the primary circuit of a converter in whose secondary the heater is located. (3.) The process of operating automatic cut-outs for Nernst lamp heaters which consists in breaking the heater circuit at two or more points. (4.) The process of operating automatic cut-outs for Nernst