382 



STAUFEN STEAM. 



(179799) ; Magazine for the History of Religion, 

 Morals and the Church (1801 6); Archives of 

 ancient and modern Ecdesia-;tie:il MUtory (1813 

 20); Archives of Ecclesiastical History, in con- 

 junction with Tzschirner and Vater (vol. i., Halle, 

 1823). He also wrote a great number of occasional 

 treat! 



STAUFEN. See Hohenstaufen. 



STAUNTON, SIE GEOEGE LEONARD, a travel- 

 ler and diplomatist, was a native of the county of 

 Galway, in Ireland. He was destined for the medi- 

 cal profession, with a view to which he studied at 

 the university of Montpellier, and took the degree 

 of doctor of physic. About the year 1762, he estab- 

 lished himself in practice in the island of Grenada, 

 in the West Indies, where he obtained the patronage 

 of the governor, Lord Macartney, who made him 

 his secretary; and he likewise held the office of 

 attorney-general of Grenada, till the taking of that 

 island by the French. His lordship, being appointed 

 governor of Madras, took Mr Staunton with him 

 to the East Indies, where he was employed in the 

 arrest of general Stuart, who had opposed the au- 

 thority of the governor. He also induced the 

 French admiral Suffren to suspend hostilities before 

 Gondelour, previously to the official announcement 

 of the peace in 1714; and he negotiated a treaty 

 with Tippoo Saib. Returning to England, the 

 East India company repaid his services with a pen- 

 sion of 300 a year; the king created him a 

 baronet, and the university of Oxford bestowed on 

 him the diploma of doctor of laws. When Lord 

 Macartney went as ambassador to China, Sir George 

 accompanied him as secretary of legation, with the 

 provisional title of envoy extraordinary and minister 

 plenipotentiary. Of that mission, and of the empire 

 and people of China, he published an Account in 

 1797 (2 vols., 4to.), which was translated into 

 French and German. He died in London, in Janu- 

 ary, 1801. 



STAUROTIDE ; a mineral species, so called 

 from rravoos, & cross, in allusion to the regular 

 crossing of its crystals, which so frequently takes 

 place. The primitive form of the crystal is a right 

 rhombic prism of 129 30', which is rarely modified 

 at its extremities, though its acute lateral edges 

 are usually truncated, converting the crystals into 

 six-sided prising. The cruciform crystals of this 

 species are of two kinds : in the first, the crystals 

 cross each other at right angles ; in the second, at 

 angles of 60 and 120. Fracture uneven or con- 

 choidal ; lustre vitreous, inclining to resinous ; col- 

 our reddish-brown, or brownish-red, very dark ; 

 streak white ; translucent ; hardness a little supe- 

 rior to that of quartz ; specific gravity 3-3 to 3-9. 

 According to an analysis, by Vaquelin, of the variety 

 from Brittany, and another by Klaproth, of the 

 variety from St Gothard, staurotide consists of 



Sili-x, 



Alumine, 



Lime, . . 



Magnesia, 



Oxide of iron, 



Oxide of manganese, 



33-00 37'. r >0 



44-00 41-00 



3-84 0-00 



0-00 0.50 



1300 18-25 



1-00 0-50 



It assumes a dark colour before the blow-pipe, but 

 does not melt. Staurotide occurs, for the most 

 part, in mica slate, and is often accompanied by 

 garnet and cyanite. It is found in single crystals 

 on St Gothard, in Switzerland, and on the Greiner 

 mountain, in Zillerthal, in the Tyrol. It is an 

 abundant substance in the United States, particu- 

 larly in the states of Maine, New Hampshire anc 

 Massachusetts. 



STAY ; :i large, strong rope, employed to sup- 

 icrt the mast on the fore part, by extending from 

 ts upper end towards the stem of the ship, as the 

 shrouds are extended on each side. 



STAYS. See Corset. 



STEALING. See Larceny. 



STEAM; the vapour of water raised to such a 

 degree of elasticity by the application of heat, as to 

 3e available to the propelling of machinery. "When 

 water, exposed to the pressure of the atmosphen , 

 "s heated to the temperature of 212, globules of 

 steam, composed of heat and water in a state of 

 combination, are formed at the bottom of the ves- 

 sel, and rising through the fluid, may be collected 

 at its surface. In its perfect state it is transparent, 

 and consequently invisible, but when it has been 

 deprived of a part of its heat by coming in contact 

 with cold air, it becomes of a cloudy appearance, 

 as when it issues from a tea-kettle. By increasing 

 the heat, the temperature of the water never rises 

 above 212, nor that of the steam which is gene- 

 rated ; the only effect being a more copious produc- 

 tion. If the water is confined in a strong copper 

 vessel, both it and the steam which is produced 

 may be brought to any temperature, and any degree 

 of elastic force 



Steam is highly elastic ; but when separated 

 from the fluid from which it is generated, it does 

 not possess a greater elastic force than the same 

 quantity of air. If, for instance, a copper vessel be 

 filled with steam only, at 212, it may be brought 

 even to the temperature of red heat, without any 

 danger of bursting ; but if water be also in the ves- 

 sel, each additional quantity of heat causes a fresh 

 quantity of steam to rise, which adds its elastic 

 force to that of the steam already generated, till 

 the constantly accumulating force bursts the vessel 

 in pieces. 



The latent heat of steam, or that quantity of 

 heat which is necessary for its existence in a state 

 of vapour, and yet is not indicated by the thermo- 

 meter is, according to the experiments of different 

 philosophers, given in the following table : 



Ruroford, 

 Thomson, 

 Lavoisier, 

 Clement, 



1051 

 1016 

 1000 

 990 



Desprete, 956 



Watt, 950 or 9GO 



Southern, 955 



Black, 800 



The mean of these results is 950, agreeing will 

 the measure obtained by Mr Watt. The estimate 

 of Lavoisier cannot be far from the truth, and af- 

 fords a most convenient number for calculation, i. e. 

 1000. 



Let us suppose that steam of the temperature of 

 212 contains 950 of heat, which is not detected 

 by the thermometer, while it retains the gaseous 

 state, its real quantity of heat will be 950 +212 

 1162; consequently, if we mix a quantity of 

 steam with 5J times its weight of water, at 32, 

 the temperature of the water will rise nearly to the 

 temperature of ebullition, because 5 X 32 -f 32 

 = 208. Hence the great utility of steam not only 

 in manufactures where great quantities of hot wa- 

 ter are required, but also for heating large buildings, 

 and for drying whatever is liable to combustion. 



The elasticity of steam, arising, no doubt, from 

 the great quantity of heat which it contains, is very 

 great, and from its extensive application as an im- 

 pelling power, it has been investigated with con- 

 siderable attention. 



Mr Watt was the first philosopher who made 

 any accurate experiments on the elasticity of steam. 

 These were performed whije he was a mathematical 



