382 



SCIENTIFIC RECREATIONS. 



Phosphorus when pure is colourless, nearly transparent, soft, and easily cut. 

 It has a strong affinity for oxygen. It evolves white vapour in atmospheric 

 air, and is luminous ; to this element is attributable the luminosity of bones 

 of decaying animal matter. It should be kept in water, and handled or 

 indeed not handled but grasped with a proper instrument. 



Phosphorus is much used in the 

 manufacture of lucifer matches, and 

 we are all aware of the ghastly ap- 

 pearance and ghostly presentment it 

 gives when rubbed upon the face and 

 hands in the dark. In the ripples of 

 the waves and under the counter of ships 

 at sea, the phosphorescence of the ocean 

 is very marked. In Calais harbour we 

 have frequently noticed it of a very 

 brilliant appearance as the mail steamer 

 slowly came to her moorings. This 

 appearance is due to the presence of 

 phosphorus in the tiny animalculse of 

 the sea. It is also observable in the 

 * female glow-worm, and the " fire-fly." 

 Phosphorus was discovered by Brandt 

 in 1669. 



It forms two compounds with 

 oxygen phosphorous acid, H 2 PO 4 , and 

 phosphoric acid, H 3 PO 4 . The com- 

 pound with hydrogen is well marked 

 as phosphuretted hydrogen, and is a 

 product of animal and vegetable de- 

 composition. It may frequently be 

 observed in stagnant pools, for when 

 emitted it becomes luminous by con- 

 tact with atmospheric air. There is 

 a very pretty but not altogether safe 

 experiment to be performed when 

 phosphuretted hydrogen has been pre- 

 pared in the following manner. Heat 

 small pieces of phosphorus with milk of 

 lime or a solution of caustic potash; 



or make a paste of quick-lime and phosphorus, and put into the flask with 

 some quick-lime powdered. Fix a tube to the neck, and let the other end 

 be inserted in a basin of water. (See illustration, fig. 388.) Apply heat ; 

 the phosphuretted hydrogen will be given off, and will emerge from the 

 water in the basin in luminous rinjrs of a very beautiful appearance. The 

 greatest care should be taken in the performance of this very simple experi- 



