156 LIVING LIGHTS. 



This should be made into balls of a convenient size, dried 

 at a moderate temperature, and kept in a crucible at a red 

 heat for about an hour. Allow them to cool slowly, and then 

 place in a glass-stoppered bottle before their heat has dis- 

 appeared. When required for use, expose them to the sun 

 or any strong light, and they will become luminous, and con- 

 tinue so for many hours. 



Another formula is : — 



Strontium sulphate (C P.) 22 parts 



Sulphur (C P.) 1 part 



Gum tragacauth q. s. 



This should be heated as above described. 



A most interesting experiment is to make a selection of 

 artificial flowers, and, having brushed them over with glue 

 or mucilage, dust them with the powder from one of the 

 balls made as described. If the flowers are exposed to the 

 sun a short time, they will emit a phosphorescent light, each 

 flower standing out in the darkness with extreme brilliancy, 

 — a striking and remarkable spectacle. 



Canton's phosphorus is easily made by calcining clean 

 oyster-shells, until they are perfectly white, in a crucible. 

 The clearer and finer portions should then be reduced to 

 powder, and placed in layers with alternate layers of flowers 

 of sulphur in a crucible. Cover, and heat to a dull redness 

 for about half an hour, then allow to cool slowly. 



Luminous "ink " or liquid can be made by placing a small 

 piece of phosphorus about as large as a pea in a test-tube 

 with a small quantity of olive oil ; hold the tube in a water- 

 bath until the oil becomes heated, and the phosphorus lique- 

 fies ; then shake it until the oil will take up no more phos- 



