C H E M I S T R Y. 



Cotnbiaa. 

 tiotu with 

 eomhut- 

 Ciblrv 



Allpys. 



Bi'n-.mli. 



froperliw. 



and has some renembhnc-e to chalk. It is tasteless 

 and insoluble in water, and is not altered by exposure 

 to the air. 



S. Most of the simple combustibles combine with 

 zinc. Hydrogen gas, procured by the action of di- 

 luted sulphuric acid on -/inc. holds a little of the 

 metal in solution, which it gradually deposites. 



Carbon was considered as an occasional constitu- 

 ent of zinc, and supposed to occasion the appearance 

 of the black powder which separates when zinc is 

 dissolved in sulphuric acid. But on examining this 

 powder, it was found a mixture of copper and lead. 



Phosphuret of zinc may be formed by dropping 

 bits of phosphorus upon melted /inc. It has a 

 considerable resemblance to lead. It is somewhat 

 malleable. Phosphorus combines likewise with the 

 oxide of zinc. 



Sulphuret of zinc exists native in considerable 

 quantity, and is known by the name of blende. It 

 may be formed by fusing a mixture of sulphur and 

 oxide of zinc. 



4. Zinc does not unite with the simple incombus- 

 tibles, but it combines with the metals, and forms al- 

 loys, some of which are of great importance. 



It renders gold brittle, even when added in a very 

 minute proportion. It melts readily with platinum, 

 and renders it brittle. Silver readily combines with 

 it, and forms a brittle alloy. Mercury easily amal- 

 gamates in any proportion when poured upon hot 

 ainc. The amalgam is used to increase the energy 

 of electric machines. 



Zinc combines with copper, and forms one of the 

 most useful of all the alloys, namely brats. It is 

 prepared by mixing oxide of zinc, charcoal powder, 

 and granular copper, and heating them sufficiently 

 in a crucible. Brass is yellow. The proportion of 

 y.inc which it contains varies somewhat. In some 

 British manufactured it amounts to one-third, while 

 in Germany and Sweden it is said not to exceed one- 

 fourth or one-fifth, brass is much more fusible than 

 copper. It is malleable while cold, but becomes 

 brittle when heated. It is ductile, may be drawn 

 into fine wire, and is much tougher than copper. 

 When zinc in the metallic state is melted with cop- 

 per, the alloy is known by the name of pinchbeck, 

 prince* t mrttil, 1'riiirr Jtujterl's metal. The colour 

 of pinchbeck approaches more nearly to that of gold, 

 but it is more brittle than braes. 



Zinc cannot easily be alloyed with iron. The al- 

 loy is hard and white, and somewhat ductile. Tin 

 and /inc easily unite. The alloy is hard and ductile. 

 Lead and zinc may be united by fusion. 



SECT. XV. OfKismuth. 



This metal was unknown to the ancienls. It was 

 well known in Germany at the beginning of the 16th 

 century. But chemists were long in reckoning it a 

 peculiar metal. 



1. Bismuth is of a reddish white colour, and al- 

 most destitute of taste and smell. It is composed 

 of broad brilliant plates adhering to one anothei. It 

 it harder than silver. Its tpeciiic gravity is 9.822. 

 When hammered cautiously, its density it increased, 

 kut it breads when etruck smartly. It cannot be 



Element* 

 of 



drawn out into wire. A rod of one-tenth inch dia- 



meter is capable of supporting about 29 Ibs. It melts 



at 476", and may be distilled over in close vessels. -^"" 



When cooled slowly, it crystallizes in parallelepi- 



ped*. 



2. It tarnishes in the air, but is not altered when Oxidei. 

 kept under water. When kept melted in an open 

 vessel, it is gradually converted into a yellow powder. 



In a strong red heal it lakes fire and burn', with a 

 faint blue Hame, and emits a yellow smoke. This, 

 when collected, is a (/<//> oxide. It is composed of 

 about 89.3 bismuth, and 10.7 oxygen. This is the 

 only oxide of bismuth at present known. It is taste- 

 less and insoluble in water. When heated it melts 

 into a brown glass. 



3. Bismuth has not been combined with hydrogen Phosphtu 

 or carbon. It does not seem capable of combining rrt> 



in any notable proportion with phosphorus. But it 

 unites very readily with sulphur by fusion. The sul- 

 phuret is bluish grey, very brittle and fusible, and 

 crystallizes in four-sided needles. It is. composed of 

 about 85 bismuth and 15 sulphur. 



4. Bismuth does not unite with the simple incom 

 bustibles, but it combines with the metalc , and forms 

 alloys not hitherto applied to any useful purpose. It 

 renders gold, platinum, and silver, brittle. It amal- 

 gamates readily with mercury. When the mercury 

 exceeds, the amalgam is fluid, and has the property 

 of dissolving lead, and rendering it also fluid. Bis- 

 muth renders copper and iron brittle. It facilitates 

 the fusion of tin and lead : a mixture of eight parts 

 bismuth, five lead, and three tin, is called fusible me- 

 tal, because it melts at 212. Bismuth does not com- 

 bine with zinc. 



Alloy*. 



The 



SECT. XVI. Of Antimony. 



lie ancients were acquainted with some of the Antimony. 

 ores of antimony, but it does not appear that they 

 knew the metal itself. Who first extracted it from 

 its ores is unknown. But the process is first describ- 

 ed by Basil Valentine. 



1. Antimony is of a greyish- white colour, aad Properties*, 

 has considerable brilliancy. Its texture is laminated, 



and exhibits plates crossing each other in every di- 

 icction. It is as hard as silver. Its specific gravity 

 is 6.712. It is very brittle, and may be easily re- 

 duced to powder in a mortar. It melts at 810, or 

 when just red hot ; and, when cooled slov.lv, forms 

 oblong crystals perpendicular to the internal surface 

 of the vessel in which it cools. 



2. When exposed to the air it loses its lustre, but Oxidei. 

 undergoes no other change. Neither is it altered by 



cold water, but at a red heat it decomposes water, 

 and combines with its oxygen, while hydrogen gas 

 is emitted. When heated iu an open vessel it gradu- 

 ally combines with oxygen, and evaporates in a white 

 smoke, which, when collected, was formerly cal- 

 led argentine Jlowers of antimony. When sudden- 

 ly heated, antimony burns, and is converted into the 

 same white oxide. Two oxides of antimony are 

 known. 



The protoxide may be obtained thus. Dissolve 

 antimony in muriatic acid, dilute the solution with 

 water ; a white powder falls, wash it and boil it in 



