FUSIBILITY 



3386 



FUST 



Fusibility. Name given to that 

 physical property by virtue of 

 which matter may be melted or 

 rendered fluid if heated to a suffi- 

 ciently high temperature under 

 suitable conditions. It is obviously 

 a very valuable and important 

 property, as it is solely due to it 

 that objects can be cast in metal. 

 It thus constitutes very largely the 

 foundation of the art of metal- 

 lurgy. While all the metals are 

 fusible they melt at very different 

 temperatures, ranging all the way 

 from =39 C. (=70 F.), the melt- 

 ing point of solid mercury, to 

 1,740 C. or 3,167 F., the approxi- 

 mate temperature at which plati- 

 num melts. At whatever tempera- 

 ture the melting takes place it is 

 always accompanied by the ab- 

 sorption of heat which becomes 

 " latent " and a change of volume. 

 In most cases this change is one 

 of expansion, but bismuth, for ex- 

 ample, contracts in volume on 

 fusion. See Liquation ; Metal. 



Fusible Metals. Metal alloys 

 which melt at comparatively low 

 temperatures. Newton devised 

 such an alloy ; while one composed 

 of 15 parts bismuth, 8 lead, 4 tin, 

 and 3 cadmium, known as Wood's 

 metal, will melt at 155 F., and 

 another (Rose's metal) composed of 

 8 parts bismuth, 8 lead, and 3 tin 

 will melt at 203 F. Both these 

 metals, therefore, will melt in boil- 

 ing water. The " magic spoon " of 

 the conjuror which melts in a cup 

 of tea is made of such a metal. By 

 varying the proportions of the con- 

 stituents, alloys of tin and lead, 

 or tin, lead, and bismuth, can be 

 made which will melt at from 

 202 F. to 380 F. Some of these 

 have an important use in the 

 manufacture of fusible plugs for 

 steam boilers. These plugs, being 

 inserted in the furnace plates of a 

 boiler, will melt if the plate, owing 

 to any circumstance shortness of 

 water or scaling becomes dan- 

 gerously overheated, and, by per- 

 mitting the steam to escape, may 

 prevent a serious accident. They 

 are also of use in electrotyping on 

 account of their property of ex- 

 panding on cooling, and so giving 

 clean-cut impressions of moulds. 

 See Alloy. 



Fusil. French term for the 

 infantry magazine rifle, e.g. the fusil 

 Lebe.l ; also a light form of flint lock 

 musket formerly used in the British 

 army. In 1857 a Serjeant's fusil 

 was issued weighing 8 Ib. 10 oz. 

 to fire the Enfield rifle ammunition, 

 and in 1858 a smooth-bore fusil 

 weighing 7 Ib. 12 oz. was issued to 

 Serjeants of native Indian regi- 

 ments. Probably the original was 

 the fusil mousquet of Vauban, 

 which was so contrived that in case 



the flint did not strike fire, the 

 powder might be ignited by means 

 of a small match which was fixed 

 to the breech. The word, derived 

 from late Lat. focile, a steel for 

 kindling fire, originally had the 

 same meaning in French. See Fire- 

 arms ; Flint Lock ; Matchlock. 



Fusil. In heraldry, an elongated 

 lozenge. A fusil may be pierced. A 

 shield divided by diagonal lines 

 crossing each other so as to form 

 acute pointed lozenges is said to be 

 "fusily." See Lozenge. 



Fusilier. Formerly the designa- 

 tion of special bodies of troops 

 equipped with a fusil or light flint 

 lock musket at a time when the 

 matchlock was the standard 

 military fire-arm. It is now only 

 the distinctive regimental name of 

 certain corps of infantry who are 

 armed exactly the same as inf antry 

 of the line. 



The first mention of fusiliers 

 occurs about 1643, when they 

 were organized as companies dur- 

 ing the Thirty Years' War. At 

 that time they were mounted, and 

 only differed from the carabiniers 

 in that they were armed with the 

 flint lock musket. Following the 

 lead set by France, various Euro- 

 pean armies introduced these 

 troops of fusiliers between 1670 

 and 1680 to act as an escort for the 

 artillerymen, who at that time 

 were hired by contract for the 

 campaign, an escort being con- 

 sidered desirable not only to pro- 

 tect them from hostile attack, but 

 also to keep a close watch on them 

 in case of treachery. As the cannon 

 were served with loose powder 

 from open barrels, it was not safe 

 for the escort to be armed with ' 

 muskets requiring the use of burn- 

 ing match ; consequently the 

 fusiliers were detailed for this duty. 



The general adoption of the 

 flint lock musket as the standard 

 military fire-arm made unneces- 

 sary the use of special troops as 

 artillery escort, and, owing to the 

 fusiliers having become accus- 

 tomed to act as independent units, 

 the regiments were largely em- 

 ployed as light infantry and not as 

 line troops. The fusiliers were re- 

 garded as corps d' elite and the 

 lowest commissioned rank was 

 second lieutenant, the junior of 

 whom took precedence of all en- 

 signs ; but at present they enjoy 

 no privileges other than those of 

 the infantry. 



The senior fusilier regiment of 

 the British Army is the Royal Fusi- 

 liers (City of London Regiment), 

 formed in 1685. The Scots Fusi- 

 lier Guards relinquished the title 

 fusiliers in 1877 and became the 

 Scots Guards. Other famous 

 British regiments of fusiliers are 



the Northumberland, Lancashire, 

 Royal Scots, Royal Welch, Royal 

 Inniskilling, Royal Irish, Mun- 

 ster, and Dublin Fusiliers. The 

 distinctive uniform of British 

 fusilier regiments is the bear-skin 

 cap (often erroneously termed a 

 busby) of similar design to, but 

 smaller than, those worn by the 

 foot guards. See Army, British ; 

 also colour plate. 



Fusion (Lat. fusio, fusion). The 

 change of state from solid to liquid 

 form of a substance, occasionally 

 spoken of as liquefaction. The tem- 

 perature at which a solid melts 

 cannot always bs determined with 

 great accuracy, especially in regard 

 to such substances as pitch, glass, 

 etc., which slowly change from the 

 solid to the liquid state as the tem- 

 perature rises. Though theoretic- 

 ally the fusion point of a solid is 

 the same as the freezing point of 

 the liquid form of the substance, 

 the two temperatures do not 

 always coincide in practice, chiefly 

 because a substance may " over 

 cool " before the change of state 

 takes place. The fusion point of a 

 solid varies only slightly with 

 variation of pressure. See Freez- 

 ing Point; Melting Point. 



Fussen. Town of Germany, in 

 Bavaria. It is situated on the left 

 bank of the Lech, about 56 m. S. W. 

 of Augsburg. It is a popular sum- 

 mer resort and dates from an early 

 period, the Benedictine abbey of 

 S. Magnus, it is said, having been 

 founded here in 629. Its principal 

 centre of interest is the 15th century 

 castle of the bishops of Augsburg, 

 which stands on an eminence over- 

 looking the town. The church of S. 

 Magnus, dating from 1701, was con- 

 structed on an older foundation, 

 a Romanesque crypt. Near by 

 istheCalvarienberg (3,130 ft.). 



Fust OR FAUST, JOHANN (d. 

 1466). German printer. With Jo- 

 hann Gutenberg, and Gutenberg's 

 son-in-law, Peter Schoeffer, Fust, 

 who is not to 

 be confounded 

 with the Faust 

 I of German 

 I legend, was 

 I prominent in 

 f the introduc- 

 tion of typo- 

 graphical 

 printing in Ger- 

 Johann Fust, many. He was 

 German printer a wea lthy gold- 

 From a print smith of Mainz, 



and financed Gutenberg's printing 

 office there. He foreclosed on a 

 mortgage and carried on the busi- 

 ness with Schoeffer, one of the mas- 

 terpieces of this partnership being a 

 LatinPsalter,1457,theinitialletters 

 in which were printedin redand blue. 

 Fust died in Paris of the plague. 



