COMBUSTION 7 



size of a pea, and kept under water, carbon bisulphide, filter 

 paper. 



a. Pour 1 c.c. of carbon bisulphide into a test tube and drop 

 in a piece of phosphorus which has been dried with a filter 

 paper. Do not touch the phosphorus with the hands, or rub 

 it. As soon as the phosphorus has dissolved, pour the solu- 

 tion on a clean piece of filter paper and place the paper on the 

 ring. When the carbon bisulphide has evaporated, the phos- 

 phorus on the paper will burst into a flame. 



6. Repeat (a), but place filter paper on a piece of iron 

 the flat base of the ring stand. What happens ? Why ? 



Phosphorus combines very readily with the oxygen of the 

 air. In the above experiment the phosphorus is spread over 

 a large surface, so that the oxygen comes into contact with a 

 considerable amount of it at one time. Thus a large quan- 

 tity of heat is soon produced. The heat does not escape 

 from the paper, since the latter rests on the ring, and is not 

 in contact with anything else. Therefore the temperature 

 of the paper rises, and ordinary combustion takes place. 

 Oily rags, damp leaves or hay, and other material subject to 

 slow decay may set fire to buildings through spontaneous 

 combustion. Proper ventilation will aid in p/eventing danger. 



References : 



1. 1703 : 30-36. Combustion Slow and Spontaneous. 



2. Farmers' Bulletin No. 105 : 26-27. Spontaneous Combustion 



of Hay. 



a. 1701 : 17-18. Combustion. 



6. 1702:49-50. Combustion. 



c. 1704 : 17. Definition of Combustion. 



d. 1707 : 37. Definition of Combustion. 



e. 1708 : 48-49. Combustion and Oxidation. 

 /. 1711 : 5157. Combustion in General. 



g. 1713 : 51-52. The Phlogiston Theory. 



