Jan. 24.] THE NEW ZEALAND GAZETTE. 145

into a refrigerating-coil or chamber, a feed-pipe leading to said cooling-jacket, an automatic valve in said feed-pipe, and a tube connecting said refrigerating-coil with said valve whereby the supply of water to said cooling-jacket is automatically regulated by variations of pressure in said refrigerating-coil, substantially as described. (7.) In a refrigerating system, and in combination, a gas-compressor, a cooling-jacket surrounding said compressor, a condenser, a tube leading from said cooling-jacket to said condenser, a circulatory pipe-system leading into said compressor, an expansion-valve in said system whereby expansion of the contained fluid is permitted and the portion of said pipe-system beyond said valve converted into a refrigerating coil or chamber, a feed-pipe leading to said cooling-jacket, an automatic valve in said feed-pipe, and a tube connecting said refrigerating-coil with said valve whereby the supply of water to said cooling-jacket and condenser is automatically regulated by variations of pressure in said refrigerating-coil, substantially as described. (8.) In a refrigerating system, and in combination, a gas-compressor, a circulatory pipe-system leading into said compressor, a cooling-jacket surrounding said compressor, an expansion-valve in said pipe-system whereby expansion of the contained fluid is permitted and the portion of said pipe-system beyond said valve is converted into a refrigerating coil or chamber, means interposed between said compressor and said expansion-valve for automatically regulating the flow of fluid through said system, and means for automatically regulating the flow of water for cooling and condensing the refrigerating-gas, both said means being connected with and operated by variations of pressure in said refrigerating-coil, substantially as described. (9.) In a refrigeration system, and in combination, a gas-compressor, a circulatory pipe-system leading into said compressor, a cooling-jacket surrounding said compressor, an expansion-valve in said pipe-system whereby expansion of the contained fluid is permitted and the portion of said pipe-system beyond said valve is converted into a refrigerating coil or chamber, an automatic valve interposed between said compressor and said expansion-valve for regulating the flow of fluid through said system, and an automatic valve for regulating the flow of water for cooling and condensing the refrigerating-gas, both said valves being connected with and operated by variations of pressure in said refrigerating-coil, substantially as described. (10.) In a refrigerating-apparatus, the combination with a compartment of an expansion-chamber within said compartment, valve-mechanism for controlling the entrance of fluid to said expansion-chamber, an exhaust-pipe leading from the expansion-chamber, a pump connected to said exhaust-pipe, a regulator also connected to said exhaust-pipe, a condenser, a tank in which said condenser is located, means for supplying water to said tank, a valve in the water-supply, means and devices controlled by the regulator for actuating said valve, substantially as described.

(Specification, 7s. 6d.; drawings, 2s.)

No. 14384.—30th December, 1901.—JAMES THOMAS HUNTER, of Queen’s Chambers, Wellington, New Zealand, Engineer (nominee of Raoul Pierre Pictet, of 14, Bendlerstrasse, Berlin, Germany, Professor of the University of Geneva, and late Professor of the University of Berlin, Germany, and Manufacturer of Chloroform at Berlin). Improvements in the method of, and apparatus for, the separation of gases from their mixtures.

Extract from Specification.—The object of this invention of “improvements in the method of, and apparatus for, the separation of gases from their mixtures,” is the provision of processes and arrangements of apparatus which shall enable the separation of gases, especially those forming the air, to be accomplished more economically than has been possible by the means hitherto provided, and to enable the separation of gases to be effected completely, or to any extent which may be desirable from time to time. For convenience of description, I will first describe my invention as applied in the separation of the elements constituting air. In accomplishing the object of my invention I adopt the processes and arrangements following, namely: (1.) The atmospheric air to be separated into its constituent gases is first filtered, compressed, and freed from water, in order that all the water-vapour which it contains, and which is often considerable, may be taken away. (2.) The dry and compressed air is cooled to the temperature of its point of liquefaction—namely, about -194° centigrade. (3.) The condensed and liquefied air is filtered to remove the solid carbonic acid which it holds in suspension. (4.) The liquid and filtered air is evaporated again in order to separate first the more volatile constituent—namely, nitrogen—and afterwards the less volatile constituent—namely, oxygen. (5.) The evaporation of the liquid air is utilised for the liquefaction of the compressed air to be separated into its constituent gases. (6.) An arrangement enabling the pressure of liquefaction to be regulated in order to insure a continuous working of the apparatus. (7.) An arrangement which, without needing attention, when once adjusted will permit the separated nitrogen and oxygen to leave the apparatus in such condition as to have the commercial or industrial value requisite from time to time, and also to permit the escape of mixtures of gases too nearly resembling atmospheric air. For the filtration of the air to be separated into its constituent gases I employ cotton-wool or other suitable material, and (which is of importance) I do not allow the air to traverse the filtering-material at too great a speed. In order that this may be efficiently accomplished I provide a chamber of relatively large section, to which the air to be operated upon is led by means of a pipe of any suitable material, or in any other suitable manner, and provided with two or more partitions, perforated or made of wire gauze, so as to be divided into a suitable number of compartments, one or more of which is or are filled with cotton-wool or other suitable filtering-material, so placed that there are no parts through which the air can pass without being filtered. Two or more filters may be arranged, so that one or more may be put into or out of action from time to time, and so that the filtering-material may be changed without interruption of the action of the other parts of the apparatus employed. A pipe or passage, or pipes or passages, of any suitable kind is or are provided to convey the filtered air to an apparatus by which it is to be compressed.

[NOTE.—The number and length of the claims in this case preclude them from being printed, and the foregoing extract from the descriptive part of the specification is inserted instead.]

(Specification, £1 8s.; drawings, 2s.)

No. 14386.—30th December, 1901.—ARTHUR AUGUSTUS BROOKS, Engineer, and GEORGE ANDREW WATSON, Merchant, both of 23, Tower Buildings, Liverpool, Lancaster, England. Improvements in or connected with photographic cameras.

Extract from Specification.—This invention relates to photographic cameras, and especially to that part of the camera in which the sensitised plates or films (hereinafter termed “films”) are contained and exposed to the object through the lens, and usually termed “dark-slide and change-box,” and our invention consists in a new constructive arrangement which forms a combined change-box, film-magazine, and dark-slide, by the construction, arrangement, and use of which a dark-room is only required by the operator for the purpose of developing and fixing the image on the films after exposure, as, in accordance with the system under which the operations are carried out, films to a convenient number are packed in cases adapted to fit in the change-box, and each case is adapted to be retained therein until all the films have one by one been withdrawn, exposed, and returned to the case again while it remains in the camera or change-box; which case can then be removed, and a fresh one containing films can be substituted for it. After the films have been removed in a dark-room from the case after exposure, the case, being cheaply made, is not further required. The chief object of this invention is to obviate the necessity of a dark-room for the purpose of charging the camera, dark-slide, or change-box, especially when a large number of films are required for immediate use. In accordance with the system upon which our invention is based, we first adapt the already sensitised films of any standard size to a case or magazine formed to hold and to retain, say, one dozen such films. We make a dark-slide in which the shutter, or light-excluding sliding-cover, is formed as a hollow case or sheath adapted to receive the said magazine without the lid or cover thereof, and in which, by means of suitable mechanism provided, the lid of the magazine is first removed without admitting light to the said dark-slide or change-box, and the plates or films are exposed to the object through the lens, and received again into the magazine by the sliding in and out of the said shutter. When all the parts composing the dark-slide or change-box are assembled, and the latter is attached to the back of the camera in the usual way, in order to expose a film the shutter is drawn out and a film is left behind in the frame or case of the dark-slide or change-box, and upon depressing the shutter the said film is forced flat against the rim round the exposure-aperture. After exposure, in order to receive the film back again into the magazine the shutter is again drawn out, and upon a second time depressing it the film is guided into the magazine. The operation of exposing a film and taking it back into the magazine again is completed in four movements in and out of the shutter.

[NOTE.—The number and length of the claims in this case preclude them from being printed, and the foregoing extract from the descriptive part of the specification is inserted instead.]

(Specification, 15s.; drawings, 4s.)