FIRECLAY 



31 58 



FIRE ENGINE 



In 1833 the London insurance 

 companies combined, and formed 

 the London fire brigade under the 

 command of James Braidwood, 

 who built the first steam fire 

 engine and was killed while at a 

 fire near London Bridge in 1861. 

 In 1866 the Metropolitan Board of 

 Works took over the entire London 

 organization, which in 1918, under 

 the L.C.C., comprised 79 land 

 stations, 3 river stations, and 

 6 ambulance stations, with 75 

 motor fire engines, 81 motor fire 

 escapes, 5 motor hose tenders, 8 

 horsed fire engines, 18 horsed fire 

 escapes, 4 electrically driven turn- 

 table ladders, 19 long ladders, 

 9 motor ambulance vans, 16 motor 

 cars, 4 fire floats on the river and 

 4 steam engines on rafts, 60 miles 

 of fire hose, and 1,582 street fire 

 alarms. The personnel comprised 

 1,297 firemen and drivers and 

 58 ambulance attendants, with 

 three principal and one chiei officer. 

 The horsed turn-out was abolished 

 in 1921. 



All important cities and towns 

 now maintain more or less efficient 

 fire brigades, though the number, 

 character, organization, and equip- 

 ment of the units of the brigades 

 vary considerably. In the larger 

 cities and towns they are composed 

 of paid officials, while in the smaller 

 ones voluntary workers usually 

 man the brigade. 



Fireclay. Material so called 

 from the high refractoriness of the 

 articles made from it, i.e. its 

 quality (when manufactured) of 

 resisting intense heat, and its 

 freedom from splitting when ex- 

 posed to rapid changes of tempera- 

 ture. The determining factor of 

 the refractoriness is the chemical 

 composition of the clay, which 

 contains but small quantities of 

 fluxing impurities (such as iron, 

 lime, magnesia, alkalis), and very 

 little free silica. A " proximate " 

 analysis of a typical Scottish fire- 

 clay shows the following per- 

 centages : Clay substance, 85 '42 ; 

 quartz, 13*42 ; felspar, 1-16. Fire- 

 clays should dry and fire without 

 cracking and have an open texture 

 to resist alternate heating and 

 cooling. In the manufacture of 

 some fireclays sawdust is mixed 

 with the clay and is burnt on 

 firing, leaving the open porous 

 texture required. The minimum 

 fusion point for a fireclay is usually 

 taken at about 1,600 C. 



Fireclays abound in the British 

 coalfields. Often the finest clay is 

 found at the depth of many feet, 

 and underlying or alternating with 

 coal-seams. - The beds do not 

 usually exceed two feet in thick- 

 ness. Deposits are worked in 

 Cornwall, Devon, Dorset, and else- 



where in the S. of England. Fire- 

 clay from Stourbridge, in Worces- 

 tershire, said to have been worked 

 in the 16th century, is largely ex- 

 ported on account of its excellent 

 qualities. See Brickmaking. 



Fire Command. Unit in coast 

 defence artillery. In every fortified 

 area the efficiency and general 

 readiness for action is entrusted 

 to an officer, usually of field rank, 

 who, as fire commander, is re- 

 sponsible for the fire control of all 

 batteries and groups in the area. 

 It is for him to organize and decide 

 upon the measures to be adopted 

 in the event of attack, and he 

 orders the commencement and 

 cessation of fire on the target, 

 directing which forts or batteries 

 shall engage individual enemy 

 vessels, and what tactics shall be 

 employed to prevent a bombard- 

 ment or landing. See Artillery. 



Fire Control. System under 

 which a warship's guns are used in 

 action. Fire is controlled from a 

 station aloft, ranges, etc., being 

 passed down to the gun crews. 

 The gunnery officer from his post 

 aloft controls a ship's armament 

 at will, his orders going through a 

 transmitting station to all parts of 

 the vessel. Director firing is the 

 most scientific phase of gunnery, 

 and its methods are confidential. 

 All turrets, i.e. the armoured 

 positions wherein the big guns lie 

 in pairs, are indicated by a letter 

 for fire contro) purposes, and the 

 gunnery officer can use the weapons 

 singly or in groups at his discre- 

 tion. See Gunnery. 



Firedamp. Name given by 

 miners to the most important of 

 the gases which are found occluded 

 in the crust of the earth. It is the 

 carburetted hydrogen or marsh 

 gas (CH 4 ), which appears in coal 

 mines. When diluted with air in 

 certain proportions it forms a 

 mixture which will explode with 

 great violence if lighted either by 

 a flame or by contact with an in- 

 candescent surf ace. Such an explo- 

 sion occurring in a coal mine may 

 kill the workers either directly, 

 by its mere mechanical violence, 

 or indirectly, by destroying the 

 workings or machinery of the mine. 



Like marsh gas itself, firedamp 

 has been formed by the decompo- 

 sition of vegetable matter. All 

 beds of coal are more or less porous, 

 being traversed by numerous 

 seams, while pockets may occur 

 here and there. In many cases 

 firedamp has accumulated in a bed 

 or in adjacent strata until it has 

 attained a considerable pressure. 

 A stroke of a pick or a drill or the 

 falling of a "block of coal may sud- 

 denly release this gas, which may 

 be distinctly heard escaping. If the 



barometer is low, that is if the nor- 

 mal pressure of the air in the work- 

 ings becomes reduced, the gas will 

 the more readily tend to escape ; 

 hence the importance to miners of 

 weather forecasts or warnings. 



The proportion of air needed to 

 make an explosive mixture varies 

 according to the composition of the 

 gas itself, which may contain other 

 gases, particularly oxygen and ni- 

 trogen, and still more according to 

 the state of the atmosphere of the 

 mine, e.g. the amount of coal 

 dust in the air. The propor- 

 tion may range from one part of 

 the gas to from seven to fifteen of 

 air. A dangerous accumulation of 

 the gas may thus be recognized by 

 a change in colour of the flame of 

 a miner's safety lamp, the use of 

 which, to the exclusion of naked 

 lights, is imperative in all mines 

 where any large quantity of fire- 

 damp may suddenly appear. See 

 Mining ; Safety Lamp. 



Fire Door. Steel or iron door of 

 a furnace through which fuel is 

 passed. In some cases the doors 

 are arranged to hinge open, and in 

 others to slide across the opening, 

 and hand-levers are fitted for open- 

 ing and closing them. See Furnace. 



Fire-eating. Branch of the 

 juggler's art. It includes exhaling 

 or swallowing flame, holding red- 

 hot iron between the teeth, drink- 

 ing molten substances, and similar 

 pretensions. A writer of the 2nd 

 century described breathing from 

 the mouth of flame and smoke as 

 arising from inflammable matter 

 inside a nutshell wrapped in tow 

 In 1672 Evelyn saw Richardson 

 chew and swallow glowing coals and 

 brimstone, besides pouring molten 

 lead perhaps cold quicksilver or\ 

 his tongue. In 1762 Strutt saw 

 Powell broil a piece of beefsteak 

 upon his tongue with glowing char- 

 coal placed beneath it. In 1814 

 Josephine Girardelli claimed to put 

 molten lead into her mouth and to 

 spit it out marked with her teeth. 

 These effects were produced partly 

 by utilising unfamiliar physical and 

 chemical principles, partly by 

 sleight of hand. 



Fire Engine. Particular kind 

 of water-pumping machine used 

 for the purpose of throwing a 

 stream or streams of water on to a 

 fire to extinguish it. Fire engines 

 were among the earliest applica- 

 tions of mechanical science to use- 

 ful purposes. Hero of Alexandria, 

 the inventor of the first steam 

 engine, about 150 B.C., describes 

 what he calls a " siphon " used in 

 his time to put out fires. 



This apparatus, in its essential 

 ideas, was identical with the com- 

 mon manual fire engine developed 

 slowly during the centuries and 



