will precipitate the copper, and by that means become covered with a stratum of brilliant metallic copper. RATIONALE...The phosphorus has a stronger affinity for oxygen than copper has; it therefore deoxydizes the solution of this metal, and the copper re-appears in its metallic state. M. Schnaubert has lately examined the action of phosphorus in metallic solutions, from which it appears that the solutions of gold, silver, mercury, lead, tin, and manganese, are all deoxydized by phosphorus, and that, when reduced, in many cases again unites to another portion of the phosphorus, forming phosphurets, as is the case in the deoxydizement of the solutions of silver, mercury, and tin. EXPERIMENT Χ. A luminous fluid which throws out flashes of light. Water boiled with a little phosphorus for a few minutes, and preserved in a well-corked phial, becomes luminous in the dark. Long cylinders of glass, filled two-thirds with this solution a little warmed, and then agitated, discharge flashes of light in all directions into the air. RATIONALE.... Part of the phosphorus is dissolved by the water, and remains in combination with it so long as this fluid is at rest, but becomes disengaged when the water is agitated; it then burns, and exhibits the luminous appearance. EXPERIMENT XI. Phosphorized mercury. May be prepared by dissolving phosphorus by trituration in a mortar, in as little oil of cloves as possible, and then uniting this mixture to mercury, by a continual agitation. Long cylinders filled with this compound become luminous when shaken in the dark. RATIONALE....A simple spontaneous combustion of minutely divided phosphorus. VOL. I. *Gatling's Faschenbuch, 1804, v. i. p. 99. COMBINATION OF PHOSPHORUS WITH METALS. EXPERIMENT I. Phosphuret of arsenic. Phosphuret of arsenic may be obtained in the following manner: Take two parts of metallic arsenic, reduce it to an impalpable powder, put it into a Florence flask, and pour over it six of water, and then add one of phosphorus. Place the flask over the lamp-furnace, and apply a gentle heat for at least three hours, taking care to supply the water as it evaporates. The phosphuret of arsenic thus obtained is of a brilliant gray colour; it may be freed from the adhering or superfluous phosphorus, by squeezing it through a fine muslin, under the surface of heated water. EXPERIMENT II. Phosphuret of Copper. To obtain phosphuret of copper, let the finest copper wire that can be obtained be coiled up into a ball, and heated to redness in a crucible, and then let fall on it pieces of phosphorus, until the copper melts. The phosphuret thus obtained is of a yellowish white colour: on being broke, it exhibits a crystalline appearance. It soon loses its lustre on exposure to the air, and becomes black. EXPERIMENT III. Phosphuret of gold. This compound may be obtained in a similar manner, by letting fall pieces of phosphorus on fine gold wire, heated to whiteness, expeditiously covering the crucible the moment the phosphorus has reached the gold wire. Phosphuret of gold is of a brass-yellow colour. It is very brittle, and exhibits, on being broken, needle-shaped crystals, EXPERIMENT IV. Phosphuret of iron. To obtain this phosphuret, let fine iron wire be heated as before, and drop into the crucible pieces of phosphorus of the size of a pea, until an union is effected, which may be known by the wire melting down suddenly. The properties of this phosphuret have not been examined. EXPERIMENT V. Phosphuret of lead. Phosphuret of lead may be prepared by melting lead in a crucible, and then adding to it phosphorus in small quantities at a time. By the first addition of phosphorus, the lead acquires consistence; but on increasing the heat, and continuing the addition, the whole becomes again fluid, which is the criterion that the process is at an end. It is of a silver white, but soon tarnishes on exposure to air. EXPERIMENT VI. Phosphuret of nickel. Phosphuret of nickel may be formed by melting nickel, and letting fall on it phosphorus. The union is very difficult to be obtained: one part of nickel requires about eleven of phosphorus. The phosphuret obtained fuses more easily than nickel. It is a white crystalline substance; its properties have not yet been examined. EXPERIMENT VII. Phosphuret of silver. Phosphuret of silver is best prepared by heating to redness, in a crucible, fine silver, rolled out as thin as writing paper, and then letting fall on it phosphorus, in small quantities at a time, until the fresh added portion of phosphorus combines with the ignited silver. Phosphuret of silver is of a white colour, and of a granulated texture. It is very hard, and soon tarnishes on exposure to air. EXPERIMENT VIII. Phosphuret of cobalt May be formed by heating to redness, in a crucible, cobalt, broken into pieces of the size of a split pea, and then adding to it gradually pieces of phosphorus of the same size, until the cobalt fuses. Phosphuret of cobalt is of a reddish-white colour: it is very brittle, and fuses more easily than cobalt. COMBINATION OF PHOSPHORUS WITH ALKALIES. EXPERIMENT I. Preparation of phosphuret of lime. Take an earthen or glass tube, about one foot long and three-quarters of an inch in diameter, and closed at one end; put into this one ounce of phosphorus, cut into pieces of the size of a pea, and freed, by means of blottingpaper, from the adhering water; then introduce into the tube three ounces of fresh burnt lime of the size of split peas, and stop the other opening of the tube loosely with a chalk stopper, to prevent the access of air. Having done this, heat to redness that part of the tube which contains the lime, by means of charcoal: when the lime may be supposed to be ignited, apply heat to the part containing the phosphorus, so as to sublime it, and to bring the vapour of it into contact with the ignited lime. The lime and phosphorus will now unite and form a mixture of a reddish brown colour, which is phosphuret of lime. This preparation has the property of making fire rise out of water, when small pieces of it are dropt into it. RATIONALE....The phenomenon is owing to a decomposition of water at the common temperature, which shall be more fully treated on under the article phosphorized hydrogen gas. REMARK....If a glass tube be made use of for preparing phosphuret of lime, that part of the tube which is heated (which may conveniently be done by passing it through the universal furnace, or through a chafing dish, filled with ignited charcoal) should be coated with clay, or loam, in order to secure it from breaking during the process. Phosphuret of lime may also be prepared, according to Von Mons,* in the following manner: Fill a small glass mattrass two-thirds with carbonate of lime in powder: put it into a sand-bath, and expose it to a heat sufficient to drive off the carbonic acid. Towards the end of the process introduce gradually a third part of phosphorus, taking care to keep the lime in a red heat. The phosphorus melts, but is prevented from burning by the remains of carbonic acid which is disengaged from the lime. When the whole of the phosphorus is introduced, shut up the mattrass with a stopper provided with a valve to let gas escape, but permit none to enter, and let the fire be immediately withdrawn. When quite cold the phosphuret is to be put in a dry bottle. EXPERIMENT II. Phosphuret of barytes. To prepare phosphuret of barytes, introduce into an earthen tube, closed at one end, first, one part of phosphorus, and then add two of fresh prepared barytes, and proceed as directed before. Phosphuret of barytes is of a brownish yellow colour: it also causes phosphorized hydrogen gas to be evolved when thrown into water. EXPERIMENT III. Phosphuret of strontia. Phosphuret of strontia may be obtained in a similar manner. COMBINATION OF PHOSPHORUS WITH CARBON. Phosphorus is also capable of combining with carbon, or rather with charcoal. This compound, which has received the name of phosphuret of carbon, was first examined by Mr. Proust. It is the red substance which remains behind when new made phosphorus is strained through chamois * Journal de Chim. iii. 75. |