January 15, 1915. THE COLLIERY GUARDIAN. 125 Defective earthing has therefore been responsible for very closely 50 per cent, of the deaths due to electric shock below ground. Imperfect insulation of cables has been responsible for 37 per cent, of such deaths. Summary of Fatal Electric Shock Accidents in 1913 at Deaths. Surface accidents :— dents. (a) On three-phase systems .— Low pressure ................... 1 ... 1 Medium pressure ................ I ... 1 High pressure................... 1 ... 1 (b) On continuous current systems :— Low pressure .............. .. — ... — Medium pressure ................ — ... — Underground accidents :— (a) on three-phase systems:— Low pressure ................... 1 ... 1 Medium pressure ................ 9 ... 10 High pressure................... — ... — ('■) On continuous current systems :— Low pressure ................... — ... — Medium pressure ................ 2 ... 2 15 16 Of the accidents on three-phase systems, 13 in all, 10 were on completely insulated systems and three on systems with the neutral point connected to earth. Of the 16 persons killed by electric shock in 1913, three were coal-cutter attendants, two were surface labourers, two were underground road repairers, two were motor attendants, one was a haulage hand, one a pony driver, one a fireman, one a coal conveyor attendant, one a drawer, one a surface screen boy, and one a trained electrician. Non-Fatal Accidents in 1913. During the year 1913, 53 separate non-fatal accidents or dangerous occurrences were reported. There were no non-fatal ignitions of firedamp reported as having been due to electricity, as against one in 1912. There were, however, three underground fires as against two, and 50 electric-shock accidents causing injury to 51 persons, against 36 accidents causing injury to 36 persons in 1912. All the electric-shock accidents we > e in mines under the Coal Mines Act, as also were all the underground fires. Underground Fires caused by Electricity.—Three under- ground fires were reported as having be<-n due definitely to electricity in 1913. 'I'he first occurred on January 16 at Leven Colliery, Fife, Scotland. It was caused by the breakdown of t«o cables which were carried through the woodwork of a trap-door, and in contact therewith without effective insulation and without armouring. The fire burnt for about an hour and the woodwork of the door and some props were destroyed. No one was injured. The second fire occurred in a haulage motor house at the Duffryn Rhondda Colliery, Port Talbot, South Wales, on March 11. In order to shield the motor man from the cold intake air a piece of brattice cloth was hung behind him and in the neighbourhood of the cables running from the motor controller to the resistances. The fire was caused by a short circuit in the base of the controller which set fire to the cables referred to. The fire travelled vid their outer coverings to the brattice cloth, which, in turn, caught fire, and some of the neighbouring props were scorched, but help was close at hand and the fire was quickly extinguished. The last fire was the least serious of the three. It occurred in a pump room at Markham Colliery, Holly- bu-h, near Newport, Mon., on May 2. A short circuit, due to a breakdown of insulation at a cable dividing box, caused an arc which ignited the rubber insulation of some neighbouring cables. The fire spread to a rubber mat on the floor of the pump room, but it was readily extinguished by the application of a little sand. Electric Shock Accidents.—Of the 50 electric shock accidents causing injury to 51 persons which were reported during 1913, 30 causing injury to 30 persons took place below ground, and 20 causing injury to 21 persons took place at the surface. Of the 51 persons injured 43 were disabled for more than seven days. In three cases the victim was unconscious for some time, artificial respiration being successfully applied in each case. In four other cases the victims were very seriously injured by burns. The first of these latter occurred in the generating station at the surface of Silverwood Colliery, Rotherham, Yorkshire, on February 9. Two men were working behind a live 500-volt alternating current switchboard when one of them dropped a spanner across some live parts. The short circuit caused an arc, which badly burnt both men about the head and face. It is said that the men were working with current on, in disobedience of instructions. The second accident above referred to occurred in the generating station at Littleburn Colliery, Durham, on May 29. The victim, a contractor’s foreman, was explaining to a member of his firm how he intended to fix some conductors which were about to be fixed behind the switchboard. He had a pair of pliers in his hand, and with these he made accidental contact with some live metal. The shock caused him to fall against three bare conductors carrying 2,750-volt alternating current. He was very seriously burnt, losing his left arm. After the accident the bare conductors were effectively protected. The third accident occurred at Greenrigg Colliery, Fauldhouse, Linlithgow, Scotland, on August 19, and resulted in severe burns to the victim’s left hand and arm, due to the failure of the insulation of a trailing cable which he was handling. The system in this case was continuous current and the pressure 500 volts. The fourth accident occurred at Bargoed Colliery, Monmouthshire, on December 29. In this case the victim was a switchboard attendant, and he committed the error of attempting to examine a switch which was alive at the time, and which he knew to be alive. He short-circuited the conductors in the neighbourhood of the switch, which was carrying 3,300-volt alternating current, and was badly burnt on the left hand, face and neck as a result. Unclassified Non-fatal Accident.—An accident of an unusual character occurred at the Prince of Wales (Haigh Moor) Colliery, near Pontefract, Yorkshire, on August 25. The glass forming the peep-hole in a coal-cutter frame was blown out with such force that it caused incised wounds in the back of the attendant, who was, at the time, 10 yards from his machine. As the result of investigation and experiment it was agreed that there had been an explosion in the coal-cutter frame caused by the volatilisation of some insulating varnish, unduly heated by a short circuit in the motor armature. This short circuit also ignited the gas which formed inside the frame of the coal-cutter, and which proved to be explosive. NEW PETROL MOTOR FIRE ENGINES FOR COLLIERY FIRE AND RESCUE STATIONS IN DURHAM AND NORTHUMBERLAND. In April 1912, the Durham and Northumberland Coal Owners’ Association established a fire and rescue station in close proximity to the Elswick Works, Newcastle-on-Tyne, and during the past year they have opened three subsidiary stations, the first at Ashington, Northumberland; the second at Houghton-le-Spring, in the mid-Durham coalfields; and the third at Peases » West, Crook. In Durham and Northumberland 350 collieries are affiliated with the Coalowners’ Association and, with a single exception, in Northumberland, the whole of these collieries are now covered by the four stations, each of the pits being within a ten miles radius of one or other of the stations. The Elswick station is provided, not only with a “ Hatfield ” petrol motor fire engine capable of pumping 450 gals, per minute, but it has a special tender carrying smoke helmets, apparatus for artificial respiration, and other appliances for service in the case of underground accidents. As a result of the satisfactory service of the Elswick motor fire engine, it was decided to adopt a similar type of machine for the new stations, and these are illustrated in the accom- panying photographs. The new engines are of smaller size than that at Elswick, having pumps of a capacity of 350 gals., as against 450 gals, per minute. The three new engines are of precisely the same construction, the motors being of the latest four-cylinder vertical Merryweather- Aster type, capable of developing 50-brake horse power. A speed of between 30 and 40 miles can be obtained on the level, and hills with gradients of 1 in 6 can be ascended easily with a full load. The motor drives through multiple-disc clutch and universal shaft to gearbox, which is of specially strong construction and gives three forward speeds and one reverse. The rear wheels are driven by sprockets and steel roller chains. The chain-drive is undoubtedly the best for heavy vehicles of this kind where great strength is a most important factor. The radiator provides an exceptionally large area of coding surface, so as to allow of climbing long gradients without undue overheating. Steering is by inclined hand wheel and is irreversible and the ignition is in duplicate, magneto and battery and coil being fitted. The brakes are in triplicate, and very powerful, being specially designed to enable the vehicles to be pulled up easily when running at high speeds. They comprise (1) hand lever working expanding shoes in the drum on rear wheels ; (2) right-hand pedal brake working expanding shoes in drum on front wheels ; and (3) left-hand pedal brake working on drum on second motion shaft. The pump is entirely of gunmetal, of the treble barrel ‘ Hatfield ” reciprocating type. It is specially designed for being run by the propelling motor, to which it is geared by means of a silent chain from a pinion, driven direct from the first motion shaft, through the gear box. The power of the motor is transferred from the road wheels to the pump by a simple movement of a lever, an operation which can be instantly performed by the driver without leaving his seat, the pump being of the reciprocating type, without the use of a foot valve or any special priming arrangements whatever. The extreme simplicity of the working parts makes it specially suitable for fire brigade work. The body of the pump is constructed in one casting of triangular form, with the pump barrels at the three angles, each having a single acting plunger, all driven from a cent, al crank. This forms a most compact pump and occupies minimum space on the framework. Access to the pump valves is easily obtained through the covers at each end. of the barrels, the valves being so arranged in their relative position to the plungers that, saving the slight necessary clearances, there is practically no air space in the pump, hence its altogether exceptional efficiency on deep lifts. It is claimed that the “ Hatfield ” pump will deliver more water, at a greater pressure, for a given expenditure of power ilian any other pump employed for fire purposes. The frame of the motor chassis is of channel steel section mounted on springs and heavy artillery wheels. The springs are of steel, with roller eyes fitted to specially designed cast steel slippers, sliding on machined guides, affording extreme flexibility. All wheels are shod with solid indiarubber Dunlop tyres, those in the rear being of twin section. The chassis has been made exceptionally strong in view of the rough tracks upon which the engine may be expected to do service, and it is also specially designed with a view to eliminating road shocks. A capacious box is arranged over the centre part of the frame to carry 1,000 ft. or more of canvas hose and other gear. Boxes are also provided under the side footboards, and a portable detachable hose reel is carried at the rear. Accommodation is provided for a full complement of men sitting and standing. The machines are handsomely painted vermilion, and the name of the brigade is written on each side in gold letters. The lighting arrangements are complete, and include two head lamps, two side lamps and a rear lamp, all electrically lighted, the power being obtained from accumulators which are charged from a small dynamo driven from the first motion shaft. Grimsby Coal Exports. — Returns for the week ending January 8, 1915, show that the coal exported from Grimsby totalled 21,534 tons foreign, compared with 25,187 tons foreign and 517 tons coastwise for the corresponding week last year. Shipments :—Foreign : Aalborg, 632 tons; Aarhus, 1,899; Amsterdam, 1,096; Christiania, 658; Dieppe, 851; Esbjerg, 172; Halmstad, 1,433; Malmo, 2,811; Odense, 2,227; Oxelosund, 3,088; Skein, 2,542; Trelleborg, 1,992; and Ystad, 2,133 tons. Coastwise nil. Imports of Pit Props in 1913.—The imports of pit props into the United Kingdom during the year just closed aggre- gated 2,476,854 loads, the value being £3,259,346. The respective figures for the two preceding years were 3,451,328 loads, valued at £4,445,066, and 2,925,806 loads, valued at £3,660,388. During the month of December 133,320 loads were imported, valued at £224,592, as com- pared with 228,528 loads, valued at £273,564 in December 1913, and 148,922 loads, valued at £167,549, in December 1912. Exports and Imports of Mining Machinery.—The value of the imports of mining machinery during the last month of the year was £3,376, against £4,770 in December last year, and that of exports £48,800, against £59,975 in December 1913. It should be mentioned that these figures do not include prime movers or electrical machinery. According to destination the value of exports was as follows ;— December. To— 1912. £ 1913. £ 1914. £ Countries in Europe 8,029 .. .. 6,452 .. . 4,141 United States of America . ... 898 .. — 54 Countries in South America 4,780 .. . 3,915 .. . 2,364 British South Africa 28,444 .. . 21,702 .. .. 17,114 East Indies 5,001 .. . 12,399 .. , 6,894 Australia 3,067 .. . 2,102 .. 893 New Zealand 2,492 .. 1,149 .. 452 Other countries 20,652 .. . 12,256 .. . 16,888 The following shows the value of exports of prime movers other than electrical :— December. r 1912. 1913. 19:4. All prime movers (except electrical)— £ £ Rail locomotives 690,006 ...752,483 ... .489,935 Pumping 55,127 ... 53,067 ... 35,999 Winding 651. ... 3,432 ... 50