When the distillation is completed, take out the adapter K, and dip it into cold water. Extract the phosphorus of each receiver to clear it from the dirt it may contain. Then filter it through a chamois skin; for this purpose agglomerate it by melting it under water at 140°; when solidified by cooling, envelop it in a damp chamois skin, of which make a little knot C (Fig. 3), which is dipped immediately in a copper dish kept in the middle of a receiver A, full of water at 122°. When the fusion is complete, press the little knot with a wooden dish DD, on which you press with a lever G, G, so as to cause a very slowly graduated pressure. The melted phosphorus passes through the skin, and reassembles liquid in the bottom of the vasis.

The operation of producing phosphorus is more complete and less dangerous by filtering it while warm on animal black. The black is spread on a bed of about 5 inches on the false bottom, pierced with holes B, B, of a cylindrical receiver A (Fig. 4).

Fig. 3.

Fig. 4.

This receiver has previously been two-thirds filled with water heated to 140° by the water-bath G. The water covers the phosphorus; it filters spontaneously through the black, passes under the false bottom in D, and it can then be run out by the faucet E, put in communication by a tube with another cylindrical receiver B (Fig. 5), terminated by two hemispherical cups. This latter receiver, also heated over a water-bath D, D, has a false bottom pierced with holes, and covered with a chamois skin C, C. The receiver B being full of water, open the faucet of communication E (Fig. 4), adapted to the tube F (Fig. 5). The phosphorus displaces the water, and deposits on the chamois skin. It is covered by a bed of water A.

Fig. 5.

Then adapt the tube F to a pump, with which draw the hot water, and stamp it again in the receiver A. The pressure compels the phosphorus to go through the chamois skin, and it passes under the false bottom in E. Let it run by the tube G, to which is adapted a draught-tube, which conducts it under the water of an inferior receiver.

We see that the operation is conducted without danger, and with economy. The last operation consists in moulding the phosphorus. The process generally followed consists in forcing it up through a tube, by aspirating the air with the mouth, being careful to keep a bed of water interspered between them. Shut afterwards with the finger the upper end of the tube, which is carried immediately in a receiver full of cold water, where the phosphorus solidifies and contracts. It is extracted in the form of cylindrical translucent sticks.

Another method of moulding it is indicated by Fig. 6. The phosphorus is liquefied exactly to its point of fusion over a water-bath H, H, in an elliptical or conical vasis I, in the bottom of which is an elbowed tube, terminated by a faucet J, soldered to the partition of a receiver L, L containing water. Into the socket of the faucet a glass tube M, M, the faucet being then opened, the phosphorus runs into the tube where it comes to within 1 or 1 1/4 inches of the end, and solidifies. Shut with the finger or with an obturator N, the end of the tube. Take it out and dip it into a receiver full of cold water, so as to extract the stick of phosphorus, when replace the tube, and repeat the same operation. It is better to leave the tube M, M, fixed at the end of the faucet, and attach to the cork N a piece of copper rod. When the phosphorus is solidified around that rod, draw the cork which carries away the cylinder of phosphorus. The faucet staying open, the liquid phosphorus continues to flow into the tube, and to solidify. Thus you obtain a length of solid product limited only by the quantity of matter, and which is cut at will into sticks more or less long.

Fig. 6.

The same disposition renders the moulding in form of grains very easy. It is sufficient to pour on a shelf, at the surface of the cold water, and to the height of the tube, a bed of tepid water at about 104°, and of a thickness of two or three inches, which does not mix with cold water on account of its density; then open moderately the faucet J, so that the phosphorus can run drop by drop. It is easy to understand that every drop in traversing the cold mass solidifies, and then the phosphorus collects in the form of grains at the bottom of the receiver. This granular form is more convenient for weighing than the cylindrical.

In the above operation, a double furnace containing ten retorts, produces 24 pounds of phosphorus. The time of the full operation is four days. With four of such furnaces, by admitting 300 days' work in the year, the product will be 7200 pounds of phosphorus.

Each retort costs from 50 to 60 cents, and when of crucible earth costs 80 cents. They are used but once, for the residuum is so hard that it cannot be extracted without breaking the retort. A chamois skin lasts only once, for its pores being full of dirt the phosphorus cannot filter through it.

The chances of breaking the retort dimi-nish the production from 11 to 9 and even 8 per cent of burnt bones.