May 26, 1916. THE COLLIERY GUARDIAN. 991 and two rotary sets are also fitted, but in this case one is of 1,200 kw. capacity. Two auxiliary transformers are installed in each sub- station, connected directly across the high-tension terminals of the main transformers. Switchgear.—The sub-stations are supplied with three- phase current from the inter-connected mains system of the north-east coast power companies through the Cleveland and Durham Electric Power Company. Aycliffe is supplied at a pressure of 20,000 volts between phases through two overhead lines. The 20,000-volt switchgear is of the Reyrolle ironclad wall-operated type. The Erimus sub-station is supplied, at a pressure of 11,000 volts between phases, through underground cables connected to the power company’s system in the Middlesbrough's district, the alternating current switch- QpodbuPv •bedgef'eld Wynyapd Gi=eaTham .^gTiHinqbn Heiqhingfor Capilion Opmesby EaglescliOe ’NEWPORT Epimus Subsfahon Davlinafon Nopin Qj NERy Mam Line ■■ n • Branch Lines -.... • Eleclpified Lines MIDDLES BROUGt / Subsfalton ►AyclifFe (Q) DARLINGTON [ Bank Top ---------— JOI Fig. 1.—Map of Shildon-Newport Line. gear being of the same type as that of Aycliffe. The direct-current switchgear at both sub-stations is of the brick cell type. Track Feeders.—Each sub-station is connected to the overhead track by four positive feeders, consisting of paper insulated, bitumen-sheathed, single wire armoured cables, each 0-5 sq. m. section, laid in wood troughing run in. with bitumen. Two negative cables at each sub-station connect the track rails to the negative busbar, these cables being similar in size and type to those used on the positive side. A hand-operated travelling crane is fitted in each sub-station. Locomotives. The freight locomotives (fig. 2) were designed and built at the North-Eastern Railway locomotive works at Darlington, the electrical equipment being supplied and fitted by Messrs. Siemens Brothers Dynamo Works Limited, Stafford. They are designed to haul trains weighing .1,400 tons at a speed of not less than 25 miles per hour on the level. The engines are of the articulated truck type, in which the tractive effort is transmitted through the truck frames. The cab, with sloping ends, is supported on the centre of each truck by strong steel eastings, which embody the centre-pin bearing and side-rubbing sur- faces in one casting, securely bolted and riveted to the plates of the cab platform, which consists of four beams secured to plates at the top and bottom. The transom between the truck frames at the centre is built up of plates and angles securely riveted to the side frames of the truck. On the centre of the transom is a steel cast-- ing, with which the aforesaid centre bearing engages. Rubbing pieces are fitted at each side, which bear on the- rubbing surfaces on the casting mentioned. The centre pin at one end is a good working fit in its bear- ings on the centre of the transom. At the other end provision is made for the creeping up of the trucks when passing round curves, but no allowance for movement transversely. The sloping ends are partitioned off from the cab, and contain the resistances, contactors, motor cut-out switches, multiple cut-out switches, and all high-tension electrical apparatus. The bow collectors on the roof of the cab are raised and maintained in connection with the contact wire by compressed air. The air system is fitted with a cock, the removable handle of which forms the key of the doors mentioned, and is so arranged that it can only be removed when the cock is in the exhaust position. It is therefore impossible to open the doors of the sloping ends while the bows are in contact with the overhead wire. In the cab two master controllers are fitted, one at each end. The cab also contains all auxiliary switches for controlling the air compressor and two dynamotors, which are used both for lighting and heating. It also contains the control valves for the Westinghouse brake and for air sanding. In the centre of the cab is a vertical hand wheel for the hand brake. Bow Collectors. Two bow collectors are provided on each locomotive (see fig. 2). Each collector consists of a hinged panto- graph of steel tubing, the whole being supported off the cab structure by strong corrugated insulators. Each collector has two bows, each fitted with an aluminium rubbing strip making contact with the overhead contact wire. Engine Shed. An existing engine shed at Shildon was adapted for the use of these locomotives, a sufficient portion being electrically equipped for the purpose. An automatic circuit breaker is provided, controlling the whole of the shed equipment, and each engine stall is controlled by an independent isolating and earthing switch, so that work can be safely carried out on the roof of any locomotive without interfering with the opera- tion of locomotives in adjacent stalls. Test Runs. In recent tests several journeys were made with one of the electric locomotives between Shildon and New- IS Pi • ■d- Fig. 2.—Overhead Equipment of Locomotive. port, a train of 1,400 tons of laden wagons being taken down from Shildon to Newport, and a train of 800 tons, consisting of 92 empty wagons, hauled from Newport up to Shildon, with stops on certain of the heaviest grades. The 800-ton train was stopped and started on a. grade of 1 in 103. The maximum drawbar pull during the tests reached 16 tons, the average speed on the run up from Newport to Shildon being 18-3 miles per hour, the maximum speed being 26 miles per hour. Up a grade of 1 in 230, which is 4-1 miles long, the 800-tons load of empty wagons was hauled at an average speed of 23 miles per hour. The locomotive also proved capable of hauling the 1,400-tons train on the level at 26 miles per hour, and its general operation proved satisfactory in all respects throughout the test. The principal firms responsible for carrying out the work were the following :—Locomotives, the North- Eastern Railway Company, Darlington; overhead track equipment and electrical equipment for locomotives, Siemens Brothers Dynamo Works Limited, Stafford; high-tension switchgear in sub-stations, A. Reyrolle and Company Limited, Hebburn-on-Tyne (sub-contractors to the British Thomson-Houston Company Limited, Rugby); rotary and static transformers for the sub- stations, the British Westinghouse Electric and Manu- facturing Company Limited, Manchester (sub-eon- tractors to the British Thomson-Houston Company Limited, Rugby); cranes in sub-stations, Herbert Morris Limited, Loughborough; 20,000- and 11,000-volt overhead transmission lines and cables supplying the sub-stations, the British Insulated and Helsby Cables Limited, Prescot. EXPLOSIVES IN COAL MINES. NEW ORDER. The Home Secretary has issued, under date April 26, 1916, an Order including the following explosives in the First Schedule of the Permitted List:— Black Bellite has the following composition :— J arts by weight. Ingredients. Nitrate of ammonium Tri-nitro-toluol .... Chloride of sodium... Plumbago ............ Moisture............. Not more Not less than than .. 62 ... 59 . 13'5 ... 11'5 .. 24'5 ... 2 3 5 4 ... 2 1 ... — The explosive shall be used only when contained in a case of Manilla paper, fireproofed and thoroughly water- proofed with a mixture of carnauba and paraffin waxes, with a detonator or electric detonator of not less strength than that known as No. 6; the greatest weight of the explosive which may be used in any one shot-hole shall not exceed 30 oz.; the explosive must have been made at the works of the Lancashire Explosives Company Limited, at Withnell, Lancashire. Four ounces of Black Bellite gave a swing of 2-48 in. to the ballistic pendulum, compared with a swing of 3'27 in. given by 4 oz. of gelignite containing 60 per cent, of nitroglycerine. Da Pont Permissible No. 1 has the following compo- sition — Parts by weight. Ingredients. Not more Not less than than Nitro-glycerine............... 10'5 ... 8 5 Ni'rate of ammonium .......... 69 ... 66 Chloride of sooium............ 16 ... 14 A.A. wood pulp (dried at 100° C.) 8'5 ... 6'5 Moisture...................... 1'5 The explosive shall be used only when contained in a case of parchment paper thoroughly waterproofed with paraffin wax, with a detonator or electric detonator of not less strength than that known as No. 6; the greatest weight of the explosive which may be used in any one shot-hole shall not exceed 18 oz.; the explosive must have been made at the works of E. I. du Pont de Nemours and Company, at du Pont, Washington, U.S.A., or at their works at Repeauno, New Jersey, U.S.A. Four ounces of du Pont Permissible No. 1 gave a swing of 2-82 in. to the ballistic pendulum, compared with a swing of 3-27 in. given by 4 oz. of gelignite con- taining 60 per cent, of nitroglycerine. Lady Paget, hon. director of the War Fair to be held in the Caledonian Market, London, N., on June 6 and 7, will preside over a coal stall. A considerable quantity of coal has been presented by merchants. The Lord Mayor will attend in state, and 2,000 men of the National Guard will be pre- sent. The funds of this giant fair will be devoted to the Wounded Allies Relief Committee. The British Foreign Office states that the “ Austrian officer ” who died in Portsmouth Prison at the end of November 1914 was Max Power, Heinert, or Heinricht. According to his own statements and those of his wife, he was not an officer, but a manager for a firm of coal and briquette merchants. He came to England not for reasons of ill-health, but, as his wife bad since admitted, for the pur- pose of espionage, and had established himself at Portsmouth some months before the war.