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Phosphorus

water, powder, acid, white, lime, liquid, phosphoric, temperature, air and mixture

PHOSPHORUS. This singular sub stance was accidentally discovered in 1677 by an alchymist of Hamburgh, nam ed Brandt, when he was engaged in searching for the Philosopher's stone.— Kunkel, another chemist, who had seen the new product, associated himself with one of his friends, named Krafft, to pur chase the secret of its preparation ; but the latter deceiving his friend, made the purchase for himself, and refused to corn-, municate it. Kunkel, who at this time know nothing further of its preparation than that it was obtained by certain pro cesses from urine, undertook the task and succeeded. It is on this account that the Substance long went under the name of Kunkel's phosphorus. Mr. Boyle is also considered as one of the discoverers of phosphorus. He communicated the se cret of the process for preparing it to the Royal Slciety of London in 1630. I! is asserted, indeed, by Krafft, that he dis covered the secret to qtr Boyle, having in the year 1678 carried a small piece of it to London, to spew it to the royal fami ly ; but there is little probability that a man of such integrity as Mr. Boyle would claim the discovery of the process as his own, and communicate it to the Royal So ciety, if this had been the case. Mr. Boyle communicated the process to God frey Hankwitz, an apothecary of London, who for many years supplied Europe with phosphorus, and hence it went un der the name of English phosphorus. In the year 1774, the Swedish chemists, Galin and Scheele, made the important discovery, that phosphorus is contained in the bones of animals, and they improv ed the processes for procuring it. • The most convenient process for ob taining phosphorus seems to be that re commended by Fourcroy and Vatiquelin, which we shall transcribe. Take a quan tity of burnt bones and reduce them to powder. Put 7.00 parts of this powder into a porcelain or stone-ware bason, and dilute it with four times its weight of wa ter. Forty parts of sulphuric acid are then to be added in small portions, tak ing care to stir the mixture after the ad dition of every portion. A violent effer vescence takes place, and a great quanti ty of wr is disengaged. Let the mixture remain for twenty-four hours, stirring it occasionally, to expose every part of the powder to the action of the acid. The burnt bones consist of the phosphoric acid and lime; but the sulphhuric acid has a greater affinity for the lime than the phosphoric acid. The action of the sul phuric acid uniting with the lime, and the separation of the phosphoric acid, occa sion the effervescence. The sulphuric acid and the lime combine together, be ing insoluble, and fall to the bottom.— Pour the whole mixture on a cloth filter, so that the liquid part, which is to be re ceived in a porcelain vessel, may pass through. A white powder, which is the insoluble sulphate of lime, remains on the filter. After this has been repeatedly washed with water, it may be thrown away ; but the water is to be added to that part of the liquid which passed through the filter. Take a solution of sugar of lead in water, and pour it gradu ally into the liquid in the porcelain ba son. A white powder falls to the bottom, and the sugar of lead must be added so long as any precipitation takes place The whole is again to be poured upon a filter, the white powder which re mains is to be well washed and dried. The dried powder is then to be mixed with one-sixth of its weight of charcoal powder. Put this mixture into an earth

enware retort, and place it in a sand bath, with the beak plunged into a vessel of water. Apply heat, and let it be gradual ly increased, till the retort becomes red hot. As the heat increases, air bubbles rush in abundance though the beak of the retort, some of which are inflamed when they come in contact with the air at the surface of the.water. A substance at last drops out similar to melted wax, which congeals under the water. This is phosphorus. To have it quite pure, melt it in warm water, and strain it sever al times through a piece of shamoy lea ther under the surface of the water. To mould it into sticks, take a glass funnel with a long tube, which must be stopped with a cork. Fill it with water and put the phosphorus into it. Immerse the funnel in boiling water, and when the phos phorus is melted, and flows into the tube of the funnel, then plunge it into cold water, and when the phosphorus has become solid, remove the cork, and push the phosphorus from the mould with a piece of wood. Thus prepared, it must he preserved in close vessels, con taining pure water. When phosphorus is perfectly pure, it is semi-transparent, and has the consistence of wax. It is so soft that it may be cut with a knife. Its specific gravity is from 1.77 to 2.03. It has an acrid and disagreeable taste, and a peculiar smell, somewhat resembling garlic.

When a stick of phosphorus is broken, it exhibits some appearance of crystalliza tion. The crystals are needle shaped, or long octahedrons ; but to obtain them in their most perfect state, the surface of the phosphorus, just when it becomes so lid, should be pierced, that the internal liquid phosphorus may flow out, and leave a cavity for their formation. When phosphorus is exposed to the light, it be comes of a reddish colour, which appears to be an incipient combustion. It is therefore necessary to preserve it in a dark place. At the temperature of 99° it becomes liquid, and if air be entirely excluded, it evaporates at and boils at 554°. At the temperature of 43° or 44°, it gives out a white smoke, and is luminous in the dark. This is a slow combustion of the phosphorus, which be comes more rapid as the temperature is raised. When phosphorus is heated to the temperature of it takes firi, burns with a bright flame, and- gives dot a great quantity of white smoke. Phos phorus enters into combination with oxy gen, azote, hydrogen, and carbon. Phos phorus is soluble in oils, and when thus dissolved, forms what has been called qind phosphorus, which may be rubbed on the face and hands without injury. It dissolves too in ether, and a very beauti ful experiment consists in pouring this phosphoric ether in small portions, and in a dark place, on the surface of hot wa ter. The phosphoric matches consist of phosphorus extremely dry, minutely di vided, and perhaps a little Oxygenized. The simplest mode of making them is to put a little phosphorus, dried by blotting paper, into a small phial ; heat the phial, and when the phosphorus is melted turn it round, so that the phosphorus may adhere to the sides. Cork the phial closely, and it is prepared. On putting a common sul phur match into the bottle, and stirring it about, the phosphorus will adhere to the match, and will take fire when brought out into the air.