Phosphorus

fos'for-us, a slightly yellow, translucent, waxy or brittle elementary substance. The name signifies light bearing, and is appropriate because phosphorus not only gives off light but takes fire easily. In contact with the air it gives off fumes, and emits a pale, "phosphorescent" light. For this reason phosphorus in the laboratory must be kept under water. The fumes of phosphorus are poisonous. Workmen in phosphorus factories and match factories are afflicted by decomposition of the bones. A small portion taken into the stomach causes death, but like many poisons, it is useful as a medicine in minute doses. Native phosphorus is not found free. Phosphorus is obtained chiefly from bone by processes of distillation, and is sent to market in sticks in tin tubes. About 6,000,000 pounds a year are prepared in England, France, and Sweden.

In the arts phosphorus is used chiefly in the manufacture of lucifer matches. It is a useful element in the chemical laboratory. When made into a poisonous compound called phosphorus paste, it may be spread on bread and used to rid premises of rats, mice, and cockroaches.

Phosphorus in the form of a phosphate, that is to say, in combination with lime, iron, or alum, is a necessary ingredient of productive soil. Worn out fields are lacking in either nitrogen, potash, or phosphates. Fortunately all three are present in barnyard manures. Marl charged with phosphorus is sold as a fertilizer under the general name of phosphate. Phosphates are an important element of the food of animals. They are requisite to build up animal tissue and for the nourishment of the brain and nerve centers.

The glow of phosphorus is due to slow oxidation, a quiet uniting with oxygen. Although the general name of phosphorescence has been given to this phenomenon the property of emitting a glow or light is not restricted to phosphorus. The beauty of gems, as the diamond, ruby, and sapphire, is due in part to a property of storing up light and emitting it. Common sugar has the same property. Decaying wood, known as punk, many algae, the under surface of the mushroom, the nasturtium, and the opium poppy have been observed to emit soft, delicate, more or less brilliantly colored lights readily seen in the dark.

Among animals, the jellyfish, certain centipedes, and especially the glowworm and the firefly glow fitfully in the dark. Of a quiet evening certain minute animals swarming in the sea give the wake of a ship a faint glow, intensified at times almost into a sheet of light. Even the human body has been known to glow at the moment of death. Formerly these cases of phosphorescence were supposed to be due to the presence of phosphorus, but scientists have reached a point where they are ready to declare that the glow may and does take place where there is no trace of phosphorus. In the case of animals, investigators are inclined to link phosphorescence with electricity, generated like movement by the vital forces of the body.

In case of minerals, phosphorescence is attributed to a structure that causes wave motion to change its frequency and reappear in some other form or color. The glow of punk wood, it is suggested, is due to the presence of phosphorescent bacteria.

See Matches