284 • THE COLLIERY GUARDIAN. February 11, 1916. cylinders 18 and 19, containing pistons 20, 21, connected to the valve stems 22, 23. Fluid pressure is admitted to the , cylinders.by pilot valves 24, 25, which' are connected to levers . 26, 27, one end of which is pivoted to an extension of the valve stems 22, 23. The other end of the lever 26 is con- nected by a, link 28, with one end of a floating lever 29, while the corresponding end of the lever 27 is connected by a link ■ 30, with one end of a lever 31, whose other end is articulated to the adjacent end of the floating lever 29. An intermediate .point 32 on the floating lever is connected both to the speed ' responsive device and to the volume governor, so that an . increase either in the speed of the machine or in the volume of the air entering the compressor will lower the floating lever. The sliding collar 33 of the speed governor is connected by a short lever 34, fulcrumed. at 35 to one end. of an arm 36, whose other end is connected by a link 37 to a lever 38, ful- crumed at 39, and pivoted at its other end to the stem 40, 'on which the floating disc 8 is mounted.. The arm 36 is pivoted to a short plunger 41, sliding in a stationary guide 42, and pivoted to the floating lever 29 at the point 32. A pressure responsive device is connected to the lever 31, and actuates it in correspondence with variations in the steam pressure in a stage or chamber of the turbine. The preferable construction comprises a sylphon diaphragm 43, attached to a rod 44, which is pivotally connected to the lever 31. - A pipe 45 conveys fluid pressure from the stage or chamber 16 to the diaphragm, so that upon an increase of pressure in said chamber, the spring 46 will be compressed, and the lever 31 will be forced downwardly. The means for positively tilting the floating lever 29 comprise a hand lever 47, fulcrumed at 48, and having a latch 49 co-operating with a notched quad- rant 50. The upper end of the lever is jointed to an arm 51 on the floating lever 29, in such a way as not to interfere . with the free up and down movements of the fleating lever, but at the same time enable the attendant to tilt the floating lever one way or the other by manipulating the hand lever. (Four claims.) • 24426 (1914). Improvements in or relating to Means for Breaking Down Clinker in Gas Producers and Furnaces. G. M. Gill', of 107, Shooters Hill-road, Blackheath, Kent; D. B. Donald, of 7, Trossachs-road, East Dulwich, London; and W. Jenkinson, of 13, Heath-street, Stepney, London.— Delates to machines >a.s used for breaking down or cutting away clinker in the gas producers and furnaces used for retort settings, water gas generators, and the like, of the kind set forth in Gill’s Patent No. 23862 of 1912. A device is provided for enabling the breaking down or cutting tool to effect 1435. Dynamo electric machines, and electrical systems con- , nected therewith. J. Stone and Company, and. Darker. 1448. Mine props. Mills. 1804. Steam superheaters. Bolton and Gray. : 1862. Rock drills and the like. Taylor and Loring. 1878, Method of superficially hardening steel. Sandberg. 2624. Rotors of dynamo electric machines. Sunderland . ‘ Forge . and Engineering Company Limited, Scott, and Robertson. ; 2674. Steam, turbine condensing.plant.' Contraflo Condenser - and Kinetic Air Pump Company, and Higgins. 2736, Machines for the breaking of coal or other friable material. Norton. 4096: Manufacture of fuel briquettes. Clarke. ’ 5513. Miners’ electric safety lamps. Oldham. 7227. Steam condensers., Soc. Anon.,,pour I’Exploitation. des procedes Westinghouse-Leblanc. 12340. Electric motor control systems. British Westinghouse Electric and Manufacturing Company. 13670. Rotary pump. Soc. Anon, des Turbines et Appareils du Saussois. 13983. Centrifugal, fans. Wilde., 15113. Dynamo electric machines adapted for synchronous working.’ Hunt, and'Sandycroft Limited. • 15276. Impellers of centrifugal pumps. Brown. 16804. Draught-regulating devices for chain grates. Soc. Anon, des Anciens Etablissements Hotchkiss et Cie. Complete Specifications Open to Public Inspection Before Acceptance. 1915. 9680. Apparatus for feeding pulverised or finely-divided fuel or other material. Quigley Furnace and Foundry Company. . , THE ACQUISITION OF ENEMY PATENT RIGHTS. The following list of British Patents, which have been granted in favour of residents' of Germany, Austria, or Hungary, is furnished in view of the new Patents Acts, which empower the Board of Trade to confer upon British subjects the right to manufacture under enemy patents, which right, when acquired, can be retained after the war, and is specially compiled for the Colliery Guardian by Lewis Wm. Goold, chartered patent agent, 5, Corporation- street, Birmingham. It is desirable in the first instance to obtain the latest particulars upon the Patents Register. If any patent listed has been assigned to a non-enemy pro- prietor, the law does not apply. 8154/07. Respirators. In breathing, apparatus, the inhaling pipe and the exhaling pipe are continued separately through the mouthpiece, so that both open directly into the month. Armaturen-und Maschmenfabrik “ Westfalia ” Akt.-Ges., Ger- many. ; 8155/07. Respirators. In cartridges for removing carbon dioxide from the exhaled air in breathing apparatus,- the absorbent for the alkaline liquid produced is placed substantially in the middle of each layer of the material absorbing the gas. Armaturen-und Maschinenfabrik “ Westfalia ” Akt.-Ges., Germany. 9316/07. Impregnating wood. In impregnating wood, etc., with a mixture of a heavy metal salt, such as zinc chloride or copper sulphate, and an alumi- nium salt, such as the acetate or sulphate, under hydraulic pressure, the process is carried on at a temperature of 60 to 98 degs. Cent., in order to avoid the liberation of acid and destruction of ■ the fibre, while ensuring coagulation of the albumin. E. Marmetschke and H. Bruning, Germany. 10356/07. Dynamo electric machines; field magnets; motors; . sparking, preventing. In a machine with half as many commutation poles as primary poles, those primary poles between which there is a commutation pole are spaced farther apart than the others, in order to allow room for the com- mutation pole. W. G. Schmidt, Germany (dated May 3, 1906). 10953/07. Cranes. Floating cranes, of the type employing ’ ' luffing rotary jibs, are mounted on rectangular pontoons, so that the crane post is equidistant from three sides of the pontoon, while the pontoon ’ is balanced in some cases by a special form of balance weight. A. Bode and K. Bottcher, Germany. L.* Copies of any of the above specifications can be supplied at the price of Is. post free. GOVERNMENT PUBLICATIONS. *^Any of the following publications may be obtained on application at this office at the price named post free. British Trade after the War, Report, 3|d. Local Government Board : Report of the Medical. Officer, 1914-15, 8}d. Report of the Registrar-General for Scotland, 1914, 2s. lid. COLLIERY RECRUITING COURTS, EXPLANA- TORY NOTICE, l|d. Trade .and Navigation accounts for January, Is. 4d. Friendly Societies’ Report for 1915, 2s. 6d. Acts, 1916 : Munitions of War Amendment, 2£d.; Trading with the Enemy Amendment, 2d. ; Customs War Powers, lid. Boiler Explosion Report, No. 2386, -at Ardol Limited, Selby, Yorkshire, 4Jd. PUBLICATIONS RECEIVED. ‘The Journal of the Institute of Metals” (No. 2, 1915, Vol. 14), edited by G. Shaw Scott, price 21s.; “The Journal of the Chemical, Metallurgical, and Mining Society of South Africa ” (Vol. 16, No. 5), December, price 3s.; “The Journal of State Medicine” (Vol. 24, No. 2), February, price 2s.; “Report of the Governors of the Public Library, Museum, and Art Gallery of South Australia. for 1914-15”; “Compressed Air Magazine” (Vol. 21, No. 1), January ; “ Cassiers’ Engineering Monthly ” (Vol. 49, No. 2), February, price Is.; “ Leeds University, Scholarships and Fellowships, 1916.” During an inquest at Tredegar on a collier who was killed by a fall at Ty Triste Colliery, a number of questions were asked as to the effect of' working with a coal cutter. In this case the cutter was worked by compressed air, and the men were scraping out the small coal from the holing, when without any warning, a large stone fell from the roof and struck the man on the back, pinning him down. He was dead when the stone was removed a few minutes later.—Mr. McBride (inspector of mines) asked whether the chief witness thought the cutter had anything to do with ■ the fall. His answer was that the same thing would have happened had a mandril been used. In answer to further questions by Mr. A. Onions, on behalf of the Federation, witness said the cutter had been stopped only two minutes before the fall. The roof was considered good in that particular face. The man holed the coal -about 5 ft., the width of the holing being nearly 3 yds. Witness had been working on the machine for about three months, and this was the first time any accident had happened. The Flow of Air Through Nozzles.—In a recent lecture by Capt. Thos. B. Morley, B.Sc., on “ The Flow of Air Through Nozzles,” before the Institution of Mechanical Engineers, the various forms of nozzles were compared with regard to their effectiveness for the production of jets of air having as high a mean velocity as possible, and the nature of the impact produced by a jet upon a flat plate and its relationship to the reaction of the jet, were discussed. The nozzles were of gunmetal, and the features, whose influence had been investigated, were the entrance curves, the rate of divergence after the throat, and the length. The method adopted for the measurement of the discharge consisted in determining the time rate of change of pressure and of temperature in a large closed reservoir from which air was allowed to escape into the atmosphere through the nozzle under test. The volume was found by filling a reservoir with water and then running the water into a tank in which it was weighed. The error was negligible. The author said it was 'difficult to determine the diameter to a. closer degree than 0-001 in., with a possible error in the area of 1 per cent. The methods considered for measuring the velocity of the air jets were : The Pitot tube, measurement of the reaction, and the measurement of the impact of the jet upon a surface of known form,.the most suitable being a flat plate placed normally to the jet and large enough to ensure that the air should leave the plate tangentially. The apparatus used for the determination of the impact of the jet was illustrated, and consisted of a brass plate 12 in. in diameter, fixed centrally at right angles to a spindle, carried by two parallel fiat strips of thin spring steel, clamped at their upper ends to a bracket upon a pillar, screwed to a wooden stand, a grooved pulley being mounted by delicate pivot bearings on a bracket also fixed to the stand. From an extension of the spindle a cord was passed in a direction normal to the plate, then over the pulley, and carried at its lower end to a scale pan. To measure the reaction of a jet it was necessary to have a flexible or swivelling connection between the nozzle and the air supply. To avoid the difficulty of making a joint, which should be reasonably airtight, and yet nearly frictionless, experiments were made with canvas hose as the flexible connection, then with an iron tube and a short length of hose to give flexibility at one point only, and then with a fixed horizontal pivot added, as near the flexible con- nection as possible. Both the impact and the reaction appliances were very sensitive, indicating, with care, to 0-2 oz. The chief observational error in these experiments was due to the pressure gauge, which could only be read to 0-5 lb. per sq. in. It was concluded that the impact and reaction results were on the whole correct within 1-5 per cent, at pressures of about 701b. per sq. in., and within 5 per cent, at 301b. per sq. in.