998 THE COLLIERY GUARDIAN. November 12, 1915. ABSTRACTS OF PATENT SPECIFICATIONS RECENTLY ACCEPTED. 1902 (1914). An Improved Self-contained Rescue or Breathing Apparatus for use in Mines or other Places con- taining Impure Air. J. Parker, B.Sc., Stenhouse-street, Cowdenbeath, Fifeshire.—The apparatus consists of a mouth-piece or half-mask fitted with valves of ample size, and coupled up to the inhaling and exhaling compartments of a breathing bag by very flexible rubber tubes. The exhaled air passes through a flexible tube from the bag to a purifying box containing caustic alkali for the removal of carbon dioxide and moisture. There are two passages in parallel through this box to reduce the resistance to the air. From the purifier, the air passes through another flexible tube to the inhaling side of the breathing bag. The supply of oxygen is stored at high pressure in a steel bottle or bottles, from which it passes through a very sensitive reducing valve which reduce? the pressure from the high and variable pressure in the storage bottle to a low and constant pressure, and at this low but constant pressure it then passes through a supply regulator or adjuster and thence to the inhaling compartment of a breathing bag, or to the inhaling tube leading from this bag. The energy stored in the compressed oxygen is not employed to assist in the circulation of the air through the apparatus by intro- ducing an injector device, but the resistance to the passage of the air is preferably kept so low that circulation can be performed by the action of the lungs, and that without appreciable difficulty. This result is obtained by making the tubes and valves through which the air passes of large dimensions, and by carefully avoiding bends wherever that is possible, and also by providing two passages in parallel through the purifying box as indicated above. But the special object is to arrange and construct the apparatus so that the rate at which oxygen is supplied shall at all times be definitely under the control of the user, and shall be capable of being regulated within whatever limits may be considered desirable for the individual user and for the character of the work to be undertaken. A sensitive regula- FIG. 2 26 —---- L- L_25 ~32 tion of the oxygen supply is arranged for, means being provided whereby the rate of supply can be increased or diminished in steps of one quarter of one litre per minute. The supply of oxygen can be varied in small steps to suit various grades of exertion, or differences in the quantity of oxygen consumed by different users, or by the same user at different times. But instead of adopting an automatic arrangement which puts the work of operating the reducing valve upon the lungs, a reducing valve is employed which can be easily adjusted so as to reduce the pressure of the oxygen from the high and variable pressure of that of the storage reservoir, to a low and very constant pressure above that of the atmosphere, at which constant pressure difference the oxygen then escapes into the circulating air through a nozzle which has a cross- sectional area of such dimensions that with the definite pressure difference chosen it will pass a definite minimum quantity of, say, one litre of oxygen per minute into the circulating air. This nozzle is placed so as to be permanently un- covered, and so that FIQ 3 27 FICL4 oxygen shall be delivered from it so long as the supply reservoir is delivering the gas into the reducing valve. It is preferable to maintain a constant pressure difference, and to make provision whereby any one of a series of nozzles, having different cross-sectional areas, can be uncovered, and will thus pass a definite volume of oxygen, which is in addition to that wffiich passes through the nozzle which is permanently uncovered. The reducing valve is of that known type used for reducing and regulating the pressure of gas for limelight apparatus, in which the pressure of the gas acting upon the inside of a diaphragm or bellows is made to overcome the pressure of the atmosphere together with that of a loaded spring acting on the outside of the diaphragm or bellows, and to force the diaphragm or bellows outwards, which motion is communicated to a sliding piston attached to the diaphragm, and operates the valve. But the valve has been designed in a compact form to suit it for application to this work, and the travel of the sliding piston and of the valve reduced, with the object of increasing its sensitiveness and certainty of operation. Fig. 1 is a longitudinal section through the reducing valve and regulator; and fig. 3 is a cross section through the reduc- ing valve at right angles to that shown in fig. 1; while fig. 2 shows the reducing valve and regulator in plan; and fig. 4 is a perspective view of the moving piston and valve. Fpr exceedingly close regulation of the pressure a conical metal valve 12 is used, which is made spherical at the top as shown, so that it can adjust itself to exactly fit into the conical orifice. When this conical valve is used the motion is also exceedingly small between the valve being full open and entirely closed, and the conical valve takes up a position when oxygen is passing analogous to that taken up by the valve when it is made of a plug of vulcanite. In order that a very sensitive regulation of the oxygen may be obtained, the first nozzle to be uncovered by the rotation of the plug 18, is of such dimensions as will pass one quarter of one litre of oxygen per minute at the constant pressure difference given by the reducing valve, and the next passes one half litre per minute, in this way rising by steps of one quarter of one litre per minute until a total of three litres per minute is being passed. (Two claims.) 6784 (1915). Improvements in and relating to Shale Retorts and the like. A. C. Thomson, of the Oakbank Oil Works, Mid-Calder, Midlothian.—Particularly relates to the discharge of the spent material from the bottom of retorts or gas producers for the destructive distillation of shale, coal, and other bituminous substances. Tn prior patent, No. 9944/96, a bottom piece or table arranged below the lower open end or mouth of the retort is fitted at or near its centre part, and extending across it with a blade adapted to rock on an axis along its bottom edge, and coinciding approxi- mately with the surface level of the table. The object of this invention is to provide facilities or means for enabling the clinker to be broken up without closing down the retort, and thus facilitate the discharge of the spent material. The invention consists in the combination of the aforesaid blade, and the means for rocking same, the bottom piece or table, the holes or slots in same, the passage in the front brick work of the retort, and the hopper with the discharge doors. Fig. 1 is a transverse sectional elevation of the lower end of o y a pair of retorts arranged in the one “ stack ” or housing; in the left-hand retort the section line is taken on the line 1—1 of fig. 2, while in the right-hand retort the section line is taken through the blade on the line 2—2 of fig. 2. Fig. 2 is an elevation of a part of ’ the lower end of three retorts arranged in the one “ stack ” or housing, the left-hand por- tion being shown in section, while the right-hand portion is shown in outside elevation. (One claim.) 16801 (1914). Improvements relating to Shaft, Well, and Tunnel Linings, and the like. E. L. Hann, of 6, Park- place, Cardiff, Glamorgan; and C. Kearton, of Hillside, Upstreet, near Canterbury, Kent.—Refers to ferro-concrete and like linings of shafts, wells, tunnels, and the like, and more particularly to the metallic frame work and parts of the lining. According to the invention the metal ring frames, consisting of inner and outer rings, connected by diagonal braces, are spaced apart and connected to each other by diagonal braces, so as to constitute a metal non- rigid and more or less flexible framework in which the bracings or connections of the inner and outer rings are arranged in planes at right angles to the planes in which are disposed the bracings which connect the frames together. The invention is serviceable in connection with shafts, wells, Biff. 2 Biff.4. -O' 6- -c -y -e r a. »e f- and the like, sunk by the drop shaft, underhung, or ordinary method of sinking, and also serviceable in connection with tunnels, and the like. The metallic framework is enclosed in a metallic casing composed of segments joined together, the preferred construction consisting of metal flanged plate segments welded together; the whole being of plain cylindrical or other desired endless form, or provided with circumferential corrugations. The earth wall.in some cases is provided with cavities or recesses for receiving cement, or the like, introduced behind or outside the casing, so as to more efficiently key in position the lining behind the casing. When such cavities or recesses are formed, and the casing is corrugated, the keying and connection between the casing and the earth wall is very effective. Fig. 1 is a vertical section; and fig. 2 is a sectional plan of a ferro-concrete lining constructed according to the invention; fig. 3 is a similar view to fig. 1, showing a modification; fig. 4 is a detailed view to an enlarged scale. (Five claims.) 16857 (1914). Process for the Production of Oils, suitable for Cracking, from Coal and Lignite. W. A. Hall, of The Chemist’s Club Building, 50, East 41st Street, New York, U.S.A.—Relates to a process for the carbonisation of bituminous coal and lignite for the production of oils suit- able for cracking, to yield spirit suitable for use in high speed internal combustion engines. The patentee has ascer- tained that carbonishing can be effected in a manner that will produce a product very different in physical and chemical character from any heretofore described, in that it is a thin, limpid oil, substantially free from pitch, and lacking sub- stantially all the fractions which usually boil between 110 degs. Cent, and 170 degs. Cent., and which contain the toluene-xylene series. It would appear that the volatile hydrocarbons of the coal which usually form this group are decomposed into members having entirely different boiling points, which members entirely alter the chemical constitu- tion of the total distillate. A comparatively fine division of bituminous coal or lignite is taken, preferably not more coarse than ordinary pea size, and to this is added a small amount of porous coke or the like, in granular form, prefer- ably about the size of rice, mixing these together very thoroughly. This mixture is charged into a retort, and heat applied thereto externally only until the evolution of all volatile matter substantially ceases. The heat is applied gradually in such manner that no part of the charge shall have a temperature higher than about 500 degs. Cent. The volatile matter which is evolved, and which is condensed in a condenser in the usual way, consists largely of oil of the character above referred to. The residue in the retort consists of coke or semi-coke or smokeless fuel. It is pre- ferable to conduct the carbonising operation at as near atmospheric pressure as possible, as any internal pressure greatly impairs the results, whereas any considerable depression has a tendency to draw over pitch. The per- centage of coke added will vary with the quality of the coal employed. For example, about 10 per cent, of coke appears to give the best results with an average Nottingham- shire or Warwickshire house coal, but with some more dense and pitchy coals a larger percentage of coke is required, in some cases as high as 20 per cent., or higher. A good gas coke or metallurgical coke is very suitable for this purpose. As will be understood, coke does not materially increase the ash, or impoverish the final coke or solid “ smokeless fuel ” as lime or carbonate does. In lieu of coke, any carbon- aceous substitute for coke may be used, such as breeze, charcoal, peat, etc., which will act as a solid fuel with the residue of the carbonising operation. The coke or the like appears to have a threefold effect. First it sub-divides the easily fusible mass with a far less fusible and more porous material, permitting of better circulation of the gases and volatile products. Secondly, it allows of speedy transference of heat throughout the mass. In the third place it appears to present an absorbing medium which gathers pitch from the surrounding molten coal, and holds it within the range of temperature at which the process is carried on. As high as 35 gals, of water- and pitch-free light oils have been obtained per ton of cheap bituminous house coal. (Two claims.) 18780 (1914). Improvements in or relating to Visual and Audible Signals, more particularly for use in Mines. H. Green, of Greenheys House, Little Hulton, near Bolton; and W. de M. Landon, of Green Bank, West Timperley, Cheshire.—Refers more particularly to signalling appliances in which provision is made for enabling the onsetter to give visual signals to the man in charge of the winding engine, which will confirm the signals given audibly from the same source. According to the invention improved means are provided, comprising two pairs of relays, whereby the signals, visual and audible, may be given successively by the onsetter to the man in charge of the engine, and the signals be automatically reset by any and every move- ment of the engine. The improved means may also comprise an arrangement of relays which will allow of signals being cancelled both by any and every movement of the engine, or also by a succeeding signal, while allowing a fresh signal to be given during the wind, and without such signal being cancelled until the engine restarts. The accompanying drawing illustrates diagrammatically one example of the invention in its simplest form. When the signal is given, by the onsetter at the bottom of the mine, or other station, the signalling circuit is completed through the shutter releasing relay d1 and switch j from a battery or other source of supply, not shown on the drawing. The relay d1 then attracts its armature d4 and circuit is completed from the positive of battery k1, through terminal q and movable contact d4, to the first releasing coil f, thence through terminals r, s, back to negative of battery. During this operation the indicator drop or shutter a1 falls, completing the local lamp circuit from battery c1, and lighting the first lamp c. When the circuit from the battery k1 is completed through the armature d4, the current also flows through the shutter releasing relay d2, bell k, and terminals s, back to the battery. As soon as the shutter a1 falls, contact is made with the second coil f, but before contact is established, the armature d3 has responded to the influence of the relay d2, and broken the circuit from the battery k1, therefore no current passes through the second releasing coil so long as the button is pressed by the signalman. When the signalling circuit is broken, the contacts of the relay d1 separate, while the contacts of the relay d2 come together, and on the signalling circuit being again completed, the shutter releasing circuits are completed, as before described. Owing to the inertia of the movable contact d3, however, the local circuit of the relay d2 is momentarily completed, and current flows from the positive of battery k1, terminal q, movable contacts d4 and d3, terminal t and shutter a1, to second shutter releasing coil f, thence back through terminals r, s back to battery k , but before the shutter a has estab- lished contact for the third releasing coil f, the armature d3 has responded to the relay d2 and broken the circuit as before described. This takes place with each successive signal, the momentary completion of the local circuit by the contact d3 of the relay d2 serving to drop the successive shutter. In the drawing, the first two shutters a1, a2 have been dropped, thus indicating that two rings have been given, and partially completing the circuit for the next ring. On the engine starting, the current from the dynamo, which is at first weak, excites the shutter-resetting relay ex (which delay is more sensitive than relay e2) and com- pletes the local circuit at u, of the shutter-resetting coils, current then flowing from positive battery k , terminal q. movable contacts v, u, shutter resetting coils g, and terminal s to negative of battery. As the strength of the current