June 25.] THE NEW ZEALAND GAZETTE. 1467

and the pistons being unconnected with a fly-wheel or other rotating or inertial device, the pistons being cushioned at the end of each stroke, and tool-holding means connected with the pistons. (2.) A free-piston engine characterized as set forth in claim 1, and having a casing which carries the cylinders with their pistons, a frame on which the casing is slidably mounted, and means for moving the casing and its attachments back and forth on the frame, consisting preferably of a screw mounted on the frame, which engages a nut on the casing. (3.) An engine which is characterized by being entirely self-contained, and which has free-moving pistons which are connected and arranged in opposite cylinders, an inlet-valve for each cylinder and outlet-ports for each cylinder, the outlet-port in each cylinder being opened and closed by the piston in the cylinder as it reciprocates, and mechanism for causing an explosion of the charge in each cylinder as soon as the gas is compressed in the explosion-chamber of each cylinder, and tool-holding means connected with the pistons and slidably mounted on the casing and preferably axially in line with the cylinders. (4.) In an engine such as described, sparking-plugs in the respective cylinders, and stationary contacts in the casing each of which is electrically connected with respective sparking-plugs, and a contact-blade carried by the connection between the pistons which moves alternately into contact with the stationary contacts as the pistons reciprocate and causes a spark to be produced alternately in each cylinder by the sparking-plugs. (5.) An engine which is characterized by having free-moving pistons which are connected and are reciprocated in their cylinders by the explosions of a suitable fuel, and the pistons being unconnected with a fly-wheel or other rotating or inertial device, a tool-holding bar connected with the pistons, the bar being hollow and telescoping with a tube which communicates with the water-jacket of the cylinders whereby water is supplied from the water-jacket to cool or lubricate the tool.
(Specification, 5s. 6d.; drawing, 3s.)

No. 16414.—27th May, 1903.—AGAZIO FALCONE, of Florence, Italy, Sergeant in the Italian Army. Improvements in and relating to electric-telegraph apparatus.

Claims.—(1.) Electric-telegraph apparatus in which signals or messages are transmitted by means of instantaneous or short induction currents of opposite sign, and are received by an electro-magnetic device having a polarised oscillatory member or tongue which pauses for a longer or shorter period between its strokes in accordance with the period of rest between the aforesaid instantaneous induction currents generated by the transmitter, thereby enabling the received signals to be prolonged or diminished independently of the duration of the transmitted currents, for the purposes specified. (2.) Electric-telegraph apparatus in which the transmitter is provided with an armature of the Siemens type situated in a magnetic field, to which armature partial rotary or small angular movements are imparted in opposite directions through suitable gearing by a transmitter key controlled by a spring, the movements of said key causing an instantaneous or short induced current in one direction when the key is depressed, and in the opposite direction when said key is liberated, substantially as and for the purpose specified. (3.) Electric-telegraph apparatus having its parts constructed, arranged, and combined to operate substantially as described with reference to the drawings, for the purpose specified.
(Specification, 4s. 6d.; drawing, 1s.)

No. 16415.—27th May, 1903.—TORE GUSTAF EMANUEL LINDMARK, of Björkhagen, Langholmen, Stockholm, Sweden. Improvements in elastic-fluid turbines.

Claims.—(1.) An elastic-fluid turbine wherein kinetic energy of the exhaust fluid from a turbine wheel, or from part of a turbine wheel, is transformed into potential energy so that the said exhaust is delivered to a further turbine wheel, or to another portion of the same turbine wheel, at a lower velocity but a higher pressure than those at which it left the previous turbine wheel or portion of the same turbine wheel, substantially as described. (2.) An elastic-fluid turbine according to the preceding claim wherein there is provided between the exhaust-outlet of a turbine wheel, or portion of a turbine wheel, and the inlet of a further turbine wheel, or portion of the same turbine wheel, a passage or channel the cross-sectional area of which increases in the direction of motion of the fluid therein in such wise that the velocity-energy of the elastic fluid passing through it can be transformed into pressure-energy, substantially as described. (3.) In a multiple elastic-fluid turbine, a wheel, a passage external to the said wheel of increasing cross-sectional area

in the direction of motion of the fluid therein, and receiving the exhaust from the said wheel, and a second wheel actuated by the said exhaust, the area of the outlet of the second wheel being such as to cause an increase of the pressure of the exhaust fluid in the said passage, substantially as described. (4.) In a multiple elastic turbine, a series of hollow wheels each having a central inlet and a circumferential outlet, and each, after the first of the series, actuated by the exhaust from the wheel next preceding, and an annular exhaust-passage surrounding each wheel-outlet, and having a cross sectional area increasing in the direction of motion of the fluid, the pressure of which is increased in the said passage, substantially as described. (5.) Improved elastic-fluid turbines constructed, arranged, and operating substantially as described with reference to and illustrated in Figs. 3 and 4, in Fig. 5, in Figs. 6, 7, 8, and 9, in Fig. 10, and in Figs. 11 and 11A respectively of the drawings.
(Specification, 13s. 6d.; drawings, 6s.)

No. 16416.—27th May, 1903.—CARL GUSTAF PATRIK DE LAVAL, of Stockholm, Kungsträdgardsatan 2C, Sweden, Doctor of Philosophy and Engineer. Improvements in or pertaining to the distillation of zinc and other volatile metals from material containing the same.

Claims.—(1.) Distilling zinc or other volatile metal from ore by means of an electric furnace, into which the ore is so introduced as to present towards the electric source of heat a slope or incline, the surface of which is heated by radiation from the said source of heat, and wherein the volatile constituents of the ore, escaping from the said surface, pass off through a special outlet, whilst the residues are collected at and removed from the base of the slope, substantially as set forth. (2.) Distilling zinc or other volatile metal as set forth by means of the electric furnace described.
(Specification, 5s. 6d.; drawings, 1s.)

No. 16417.—27th May, 1903.—GEORGE EVERETT HOYT, of San Francisco, California, United States of America, Mechanic. Gas or explosive engines.

Claims.—(1.) In a gas-engine, a main cylinder, a trunk-piston movable within said main cylinder forming a combustion-chamber at the outer end of the latter, a fixed trunk-piston extending within said movable piston forming a compression-chamber between it and the latter, a gas inlet and outlet in said fixed trunk-piston, and valves in said fixed trunk-piston leading to and from said compression-chamber, substantially as specified. (2.) In a gas-engine, a main cylinder, a trunk-piston movable therein forming a combustion-chamber between the two, a fixed trunk-piston extending within said movable piston forming a compression-chamber between the two latter, a horizontal partition in said fixed trunk-piston dividing it internally into two chambers or passages, an inlet-pipe for gas to one chamber, an outlet-pipe for gas from the other chamber to the combustion-chamber, and valves between the said chambers or passages respectively and the compression-chamber, substantially as specified. (3.) In a gas-engine, a main cylinder, a trunk-piston movable therein forming a combustion-chamber between the two, an extension to said combustion-chamber in which ignition takes place, a fixed trunk-piston extending within the movable piston forming a compression-chamber between the two latter, said fixed piston being divided into two chambers or passages, a gas-inlet to one passage 19, a gas-outlet from the other passage 25 to the combustion-chamber, a valve opening from passage 19 to the compression-chamber, and a valve opening into passage 25 from the compression-chamber, substantially as specified. (4.) In a gas-engine, a main cylinder, a trunk-piston movable therein, a fixed trunk-piston extending within and guiding the movable trunk-piston, a horizontal partition in said fixed trunk-piston dividing it internally into two passages, a slotted way in said partition for the cross-pin to traverse in, a cross-pin in said slot fixed in the walls of the movable trunk-piston, a forked connection between said cross-pin and the main crank-shaft, and a main crank-shaft from which the movable trunk-piston derives its motion, substantially as specified. (5.) In a gas-engine, a main cylinder, a trunk-piston movable therein, a fixed trunk-piston extending within said movable piston, supporting and guiding the latter at top and bottom, said fixed piston being flattened at the sides to form clearance spaces for the strengthening-bosses of the movable piston, bosses formed on the interior of said movable piston, and a cross-pin fixed in said bosses to form a means of attachment for the mechanism which moves the movable piston, substantially as specified. (6.) In a gas or vapour engine, an automatic igniter, the same comprising a retort or chamber suitably connected to the engine’s cylinder, a lining of refractory material within the retort or chamber, communication