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Experiment 9. If one part of oxyd of bismuth and two of muriate of ammonia be distilled, the residue in the retort will be muriate of bismuth.

Rationale. The muriate of ammonia is decomposed; ammoniacal gas is disengaged, which may be absorbed by water; the muriatic acid combines with the bismuth into a muriate.

Experiment 10. If bismuth be fused in a crucible, and small pieces of phosphorus dropped into it, a phosphuret of bismuth will be formed.

Experiment 11. If sulphur and bismuth be mixed, and melted, a compound will be produced called the sulphuret of bismuth.

Remark. Bismuth unites with the metals :

The common mixture for pewter is 112 pounds of tin, 1.5 pounds of lead, and six pounds of brass; but many manufacturers use also bismuth and antimony to compose this metal. · Bismuth is likewise generally mixed with tin for vessels of capacity, &c. as it gives to that metal a greater degree of brilliancy and hardness.

Experiment 12. Melt together 8 parts of bismuth, 5 of lead, and 3 of tin, the mixed metal will fuse at a heat no greater than 212.° Tea-spoons made with this alloy, surprise those who are unacquainted with their nature. They have the appearance of common teaspoons, but melt as soon as they are put into hot tea.

Experiment 13. If lead, zinc and bismuth be taken in equal parts, the resulting alloy will melt with so small a portion of caloric, that it may even be kept in fusion upon paper over a lamp.

SECTION XVII.

OF ANTIMONY.

Experiment 1. To obtain antimony, heat 32 parts of filings of iron to redness, and project on them, by de

grees, 100 parts of antimony; when the whole is in fusion, throw on it, by degrees, 20 parts of nitrate of potash, and after a few minutes quiet fusion, pour it into an iron melting cone, previously heated and greased.

Experiment 2. It may also be obtained by melting eight parts of the ore mixed with six of nitrate of potash, and three of acidulous tartrite of potash, gradually projected into a red-hot crucible, and fused.

Experiment 3. To obtain perfectly pure antimony, Margraff melted some pounds of the sulphurated ore in a luted crucible, and thus scorified any metals it might contain. Of the antimony thus purified, which lay at the bottom, he took sixteen ounces, which he oxydated cautiously, first with a slow, and afterwards with a strong heat, until it ceased to smell of sulphur, and acquired a grayish white colour. Of this gray powder he took four ounces, mixed them with six drams of acidulous tartrite of potash, and three of charcoal, and kept them in fusion in a well covered and luted crucible, for one hour, and thus obtained a metallic button that weighed one ounce, seven drams, and twenty grains.

The metal, thus obtained, he mixed with half its "weight of desiccated carbonate of soda, and covered the mixture with the same quantity of the carbonate. He then melted it in a wet covered and luted crucible, in a very strong heat for half an hour, and thus obtained a button which weighed one ounce, six drams, and seven grains, much whiter and more beautiful than the former. This he again treated with one and a half ounce of carbonate of soda, and obtained a button, weighing one ounce, five drams, and six grains. This button was still purer than the foregoing. Repeating these fusions with equal weights of carbonate of soda three times more, and an hour and a half each time; he at last obtained a button so pure as to amalgamate with mercury with ease, very hard, and in some degree malleable; the scoriæ formed in the last fusion were transparent, which indicated that they contained no sulphur, and hence it is the obstinate adherence of the sulphur that renders the purification of this metal so difficult.

It melts at 810', and evaporates when the heat is . raised. It is tarnished by exposure, and it readily decomposes water, as follows:

Experiment 4. If the vapour of water be made to pass over red hot antimony, a detonation will take place.

Rationale. The oxygen of the water unites with the antimony; its hydrogen is disengaged, and at this instant is inflamed.

Experiment 5. When antimony is heated to whiteness in a crucible, and in this state agitated, in contact with the air, it inflames with a sort of explosio::, and presents while burning a very singular kind of white Hame, forming what have been formerly called 'argentine flowers.

Rationale. By the combustion of antimony, it unites with oxygen, forming the white or per oxyd, or flowers of antimony. According to Thenard, antimony is capable of combining with six different doses of oxygen. The prot oxyd may be procured thus :

Experiment 6. The solution of antimony in muriatic acid being decomposed by the addition of water, and the white precipitate thus obtained being boiled for some time in a solution of potash, vill afford a dirty white powder or prot oxyd of antimony.

Rationale. The addition of water precipitates the prot oxyd of antimony, but containing a portion of the acid, from which it is separated by the use of potash.

Experiment 7. If sulphur and antimony be fused together in a crucible, a compound will be formed called sulphuret of antimony, or artificial crude antimony.

Experiment 8. If equal parts of dry phosphoric acid and antimony, with one eighth of powdered charcoal, be fused together in a crucible, a substance will be formed called phosphuret of antimony.

Rationale. The charcoal decomposes the phosphoric acid, carbonic acid is disengaged, and the phosphorus combines with the antimony.

Experiment 9. If crude antimony and nitrate of potash be deflagated in a crucible, a compound of sulphu

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ret of potash, sulphate of potash, and oxyd of antimony with sulphur will be formed.

Experiment 10. If the scoria be separated from the product of the last experiment, the remaining substance being of a liver colour, has received the name of liver of antimony, or crocus of antimony.

Experiment 11. By a similar process, but varying the proportion of the ingredients, a compound is formed, called the white calx or unwashed diaphoretic antimony.

Experiment 12. If water be added to the last mentioned compound, a preparation will be formed, called the washed diaphoretic antimony.

Rationale. The object of washing it, is to separate the saline matter.

Experiment 13. If the gray sulphuretted oxyd of antimony be fused in a crucible, we procure a beautiful transparent glass, which is called the glass of antimony. This takes the colour of the hyacinth.

Experiment 14. If antimony be ground fine, and thrown into a dry glass jar filled with oxygenized muriatic acid, it will inflame immediately, and continue to burn with great rapidity and with a brilliant white flame. The combustion affords a beautiful spectacle. See the Properties of Oxymuriatic Acid Gas.

Experiment 15. When antimony is well fused upon charcoal, and if, at the moment when its surface is not covered with any particle of oxyd, we throw it suddenly upon the ground, the globules, into which it divides in its fall, burn with a very lively flame, throwing out on all sides brilliant sparks, different from that of any other metal.

Experiment 16. Mix five or six grains of sulphuret of antimony with half its weight of oxygenized muriate of potass, and then, if a sudden stroke be given to the mixture, upon a steel anvil, it fulminates with a loud report, emitting, according to Fourcroy, a flame as brilliant and rapid as lightning.

Experiment 17. Into a boiling ley of pure potash dissolved in about three or four times its weight of water, throw sulphuret of antimony equal to a sixteenth of the

alkali employed. Stir the mixture well, and after it has boiled a little, filter it. On cooling, this liquor will deposit an abundant precipitate, which must be washed, first with cold, and afterwards with boiling water, until it becomes insipid: when dry, pulverise it and sift it through a silk sieve.

Rationale. The sulphuret of antimony is dissolved in the solution of potash; and the water at a high temperature holding more of the compound in solution than it is capable at a low one, is the cause of the subsequent precipitation as the liquor cools. This precipitate is Kermes' mineral, or the brown àntimoniated sulphur. It is said, that the compound of sulphuret of antimony and potash on being boiled in water, decomposes that fluid; the metal is oxydized and hydrogen is evolved, which combines with the sulphur; that the sulphuretted hydrogen thus formed, combines partly with the potash, and partly with the oxyd of antimony, and that the sulphuretted hydroguret of brown oxyd of antimony (Kermes' mineral) is soluble in a solution of sulphuretted hydroguret of potash at 212, but not at ordinary temperatures. Therefore, on cooling, it separates and falls to the bottom. There are other processes for preparing Kermes, which may be found in Duncan's Pharmacopea. The golden sulphur of antimony, which is similar in some respects to the Kermes, may he prepared in the following manner :

Experiment 18. Drop into the fluid in which the Kermes has been formed, either nitric, sulphuric, or muriatic acid until the precipitate ceases to appear. Or,

Experiment 19. Boil together about 2 parts of potash, two parts of sulphuret of antimony, and three parts of water; strain the liquor while warm through a double cloth, and add to it when filtered as much diluted sulphuric acid as is necessary to precipitate the sulphuret, which must be well washed with warm water.

Rationale. On boiling the sulphuret of antimony with a solution of potash, the water is decomposed in the same manner as before stated, and the sulphuretted

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