July 9, 1915. THE COLLIERY GUARDIAN 87 ABSTRACTS OF PATENT SPECIFICATIONS RECENTLY ACCEPTED. 5652 (1914). Improvements in or relating to Heat Accumulators. Maschinenbau Actiengesellschaft Balcke, of 5, Marienplatz, Bochum, Westphalia, Germany.— Relates to safety valves for heat accumulators of the “ gas- holder ” type, adapted to counteract injurious action of excessive rise or fall of pressure in the steam accumulator. According to the invention, instead of valves, pipes, which are controlled by the movement of the floating bell, in such a manner that their steam outlet or air inlet openings are uncovered by the bell. The accompanying figure shows the application of the pipe as a plunger pipe and substitute for the steam outlet valve. (Eight claims.) 5737 (1914). Improvements in and relating to Explosives. Dr. H. Stoltzenberg, of 6, Friedensburgstrasse, Breslau, Germany.—Relates to an improved process for stabilising explosives. It has been found by the applicant that, in comparison with the known stabilisers, betaine exhibits the advantage of not being destroyed by acid radicals, e.g., oxides of nitrogen, but forms additive compounds therewith; for instance, by the formation of a compound Bet6N2O3. Betaine exhibits the further peculiarity of not only forming compounds with acid radicals, but also of forming acid and per-acid compounds; for example, BetHCl and Bet2HCl, and Bet2H2Cr2O7. When exposed to a current of gaseous nitrous acid, betaine takes up about one-half its own weight of said acid. Since betaine is not decomposed, even in the warm, by the products given off during the gradual decom- position of explosives when left standing, 'and since, on the other hand, the resulting compounds can be heated far above their fusion point without undergoing explosive decomposition, it constitutes a real ideal stabiliser, which is more reliable in action than the organic compounds hitherto used, these being either decomposed or oxidised by warm nitrogen oxides or radicals of nitro-sulphuric acid. Moreover, the conditions of solubility of betaine are very favourable, on which account also it is suitable as a stabiliser. Betaine from 0*5 per cent, up to 10 per cent, may be employed as a stabiliser in all cases where acid radicals can be set free, and bring about catalytic decom- position—viz., with nitrite and nitrate explosives,, such as nitro-glycerine nitro-cellulose and organic nitro-compounds, and with all mixtures where acid substances are employed, or such substances where acids may be split off—viz., for example, chlorates, permanganates. The composition of nitrate explosives containing betaine is exemplified by the following examples :—Amikronit : 25 per cent, nitro- glycerine, 36 per cent, betaine nitrate, 38’5 per cent, wheat flour, 0’5 per cent, betaine; plagioklasit : 50 per cent, nitro- glycerine, 45 per cent, betaine chlorate, 5 per cent, betaine; cavete : 45 per cent, betaine permanganate, 15 per cent, nitro-glycerine, 35 per cent, charcoal powder, 5 per cent, betaine; somniol : 94 per cent, ammonium nitrate, 3 per cent, rosin, 3 per cent, betaine. The composition of a nitrite explosive containing betaine is exemplified by the following example :—Submikronit : 30 per cent, nitro- glycerine, 41 per cent, betaine nitrite, 28 per cent, wheat flour, 1 per cent, betaine. (Two claims.) 5746 (1914). Improvements in Respiratory Apparatus. A. B. Drager, of Moislinger Allee 53, Lubeck, Germany.— Consists in arranging a special bag for the chemicals, which is connected with the breathing bag and the mask or the like respectively by suitable flexible pipes. This chemical bag can be collapsed or pressed together from outside to separate the chemicals inside that might have caked 3?iij & Fin.3 J 4- together, and to dislodge the same, so that the air passing through will always contact with new surfaces, of the chemicals. The creation of air passages and obnoxious air spaces is thus prevented. The breathing bag itself always remains clean, and, moreover, the mixing of harmful par- ticles with the air drawn into the lungs is prevented. In fig. 1 the apparatus is shown in elevation applied to a human body; fig. 2 is a sectional diagrammatical view of the same; and fig. 3 is a similar view, showing a modifica- tion in which the pipes d and f are provided with prolonga- tions d1 and f1, which project into the bag c and are pro- vided with lateral openings, thus well distributing the air passing through the bag c. In either construction the chemical bag may be made detachable, so as to enable the replacing of an exhausted chemical bag by a fresh one. In either case the connections may be such that communication between the breathing mask and the chemical bag may be direct or indirect—that is to say, coolers, saliva collectors or the like may be interposed between said members, if desired. (Five claims.) 6061 (1914). Improvements in connection with the Removal of Ammonia from Coal Gases and the like. N. Schuster, of 7, Princes-street, Westminster, and British Coke Ovens Limited, of the same address.—Has for its object the recovery, with greater efficiency and economy than heretofore, of ammonia, in the form of sulphate of ammonia, from ammoniacal liquor obtained during the puri- fication of gases evolved in the process of distilling coal in coke ovens, gas retorts and the like. To attain this object, the ammonia is extracted from ammoniacal liquor by means of coal gas from which the heavy hydrocarbons have been removed, and for this purpose the necessary volume of gas to be employed for so extracting the ammonia is withdrawn from the main, is then re-heated, and, after being passed through an ammonia still in which it becomes heavily laden with ammonia, is returned to the main, and, together with the gas flowing through the said main, is caused to enter a saturator; the returning gas laden with ammonia is caused to re-enter the main at a pressure greater than the gas at the part of the main where the returning gas so re-enters. As compared with the employment of steam for the extrac- tion of ammonia from ammoniacal liquor, the process of ammoniacal liquor distillation as carried out by this inven- tion effects an enormous saving of heat, 'and consequently of cost of production. This saving consists chiefly of the heat known as “ latent heat,” expended for the purpose of changing the liquid state of water at 212 degs. Fahr, into steam of the same temperature. The gas for the process, according to the invention, is heated to a temperature of between 212 degs. Fahr, and 750 degs. Fahr., and if the stated minimum heat of gas is adopted, the ammoniacal liquor should be pre-heated to about boiling point. In substituting a given weight of steam required for the distil- lation of a given quantity of ammoniacal liquor at about 212 degs. Fahr, by an equal weight of gas at a temperature of 212 degs. Fahr., practically equal results are obtained with a considerably less expenditure of heat. The accom- panying drawing is a general diagrammatic view of the plant employed in the process according to this invention. (Five claims.) 13310 (1914). Improved System of Electric Signals for Main and Tail Haulage in Mines and Other Places. G. B. Burrows, of Brancepeth-terrace, Willington, Durham.— Relates to electrical signalling in mines by means of current taken from the main lighting or power cables after being suitably transformed, and consists in an improved arrangement and equipment of a series of signalling stations placed at junction and terminal points along an “ engine plane ” or haulage road, with means for transmitting aural signals to a distant station, at the same time indicating in a visual manner at the sending station. In the accom- panying drawing the improved system is illustrated by means of a diagrammatic sketch. The apparatus employed consists of a strong cast iron protective case a of a flame- tight construction, enclosing the whole of the signalling mechanism and appliances, which comprise three bells b, b1, b2, three indicating lamps c, cl, c2, selective switch d, three rapper keys e.e1,^2, telephone and speaking battery, situated at each “ off-take,” two of which are represented on the drawing. And on each landing (indicated by the letter L on the drawing) are similarly provided a bell /, lamp g, key h, telephone and speaking battery. Also in the engine-room (indicated by the leters E. R. on the drawing) are provided a bell i, lamp ;’, key k, telephone, speaking battery (not shown), and distance indicator I. The latter consists of an aperiodic low-resistance galvanometer, with a pointer making excursions over a scale which is cali- brated on site. Its operation is based on the fact that the current flowing in a circuit varies inversely as the resis- tance of the circuit. Each successive station will have a greater resistance of wire in circuit than the previous one, and therefore each station will indicate a definite position on the scale of the galvanometer. The various stations and landings above mentioned are connected to each other by multicore cables m in the case of “ gassy ” mines, or by bare wires in “ naked light pits.” Suitable ringing keys n are inserted where necessary. These perform the usual function of closing a circuit, and their use is for emergency purposes only, so that any person may give warning of an accident, such as the derailment of a train of tubs or corves, or any other such occurrence. The visual signal employed is obtained by utilising the drop in volts across an impedance coil o, for the purpose of lighting a lamp; the said lamp having electrical connections with both sides of the impedance coil. The selective switch d before referred to, situated at each “ off-take,” consists of a rotatable star or spider, mounted on a suitable base and having a lami- nated brush contact at the extremity of each arm, and insu- lated therefrom. On the base board are mounted three sector bus bars p, each having three stud contacts q placed in close proximity. The brush on each arm of the spider bridges over and connects the particular sector bus bar p with which it is in contact with one of the stud contacts q. These stud contacts may be designated as ”1,” “ Home ” and “ 2,” the whole assembly forming three distinct circuits, each having three positions. The studs “ 1 ” of the top circuit, “ 1 ” and “ 2 ” of the left-hand circuit, and “ 2 ” of the right-hand circuit, are permanently inter-con- nected with each other. The studs “ Home ” and ‘‘ 2 ” of the top circuit are permanently linked, and also the studs “ 1 ” and “ Home ” of the righthand circuit are likewise connected. The “ Home ” stud of each of the three circuits is connected through its respective bell to earth, as shown in the drawing. The switch at an off-take or station when in position “ 1 ” connects the landing (serving that particular off-take) through to the previous station. The same opera- tion connects the succeeeding station to the “ Home ” bell b2 at the operating station in order to allow signals to be received from the succeeding station when the landing is switched through. Similarly, when the switch is in posi- tion “ 2 ” the succeeding station is connected through to the previous station, and the landing is connected to its “ Home” bell b1. When “ through ” signalling operations are not being carried on at any off-take the selective switch at each off-take is left in the position “ Home ” when none of the circuits are through, but all ring on their respective “ Home ” bells b, b1, and b2. The improved system may be operated by a low-volt age transformer placed at a con- venient centre, and, as a whole, forms a standard assembly suitable for any colliery where alternating current is avail- able. (Four claims.) 18996 (1914). Improvements in Telphers, Cranes and the like Adapted to Carry Tripping Skips or Receptacles. R. Dempster and Sons Limited, of Rosemount Ironworks, Eiland, Yorkshire, and J. C. Rowlands, of the same place. —Relates to telphers, cranes and the like adapted to carry skips or receptacles on which a catch or lever is operated when it is required to discharge their contents, the hoisting ropes for the skips being wound on to a drum. The prin- cipal object of the invention is to prevent slackness or uneven winding of the tripping rope of the skip, which would otherwise be liable to overlap in winding, with detri- mental effect on its working. For this purpose an automatic slide is provided, which ensures correct winding of the tripping rope, in combination with counterweights which regulate its tension. The drum, which may be rotated by an electromotor on the telpher, is spirally grooved to receive the hoisting rope, and under or near the said drum is fitted a slide, having at one end a pulley, and at the other end a tooth engaging a part of. the spiral groove which is not at the time occupied by the hoisting rope; therefore, at each revolution of the drum the slide moves longitudinally a distance equal to the pitch of the groove. One end of the tripping rope is led around the pulley on the movable slide, and thence to the rotating drum, on which it can thus be neatly coiled as the drum rotates in one direction—that is, as the hoisting rope is being taken up, the tooth on the slide always keeping in advance of the hoisting rope during the winding-on operation, and vice versa, the noisting rope always vacating a groove before the tooth reaches it during unwinding. The tripping rope then passes around a pulley connected to a counterweight, or weights, movable in ver- tical guides located on the back of the cabin, or in other convenient position, and thence through the cabin, where the action of the said rope on the skip or receptacle is con- trolled. Fig. 1 shows, by way of example, a winding drum having the improvements applied thereto; figs. 2 and 3 are detail views on a larger scale, taken at right angles to each other, of the tooth on the slide. (Two claims.) 19191 (1913). Improvements in the Method of, and Appa- ratus for, Producing Cement and the like from Blastfurnace Slag and like Smelting Products. W. Lessing, of Menzen- berg, near Honnef - a m-Rhein, Germany.—There is used, in combination with an inclined revolving cooling drum, a scattering or disintegrating drum or wheel arranged for projecting the liquid slag into the inclined cooling drum, and having its axis arranged transversely of the axis of the cooling drum, the liquid slag being poured on to the said disintegrating drum or wheel at the elevated end of the cooling drum. A disintegrating drum or wheel, having its axis arranged as described, atomises the material much more effectively than a jet of air or steam, without tendency to produce slag wool and large lumps of slag, the granules being of the size of coarse grit, or smaller. It also flings the slag forwards, and not against the surrounding wall, so that there is no tendency to form a crust which will interfere with the working of the disintegrating drum. The air is admitted at the end at which the cooled material leaves the drum, so that the slag and the air travel in opposite directions, the air being discharged through a chimney or uptake at the end at wnich the slag enters. The disintegrating drum or wheel does not interfere with the flow of this air to the chimney. The air takes with it the