AND SCHONBEIK 65 



The very same reactions, only in a more pronounced 

 degree, can be brought about with the help of the 

 flame of an ordinary candle, by merely leading into 

 it a current of atmospheric air as in testing with the 

 blow-pipe. Thus the remarkable fact appears that 

 the results are due to the oxidizing, and under no 

 circumstances to the inner or reducing flame. The 

 simplest method of demonstrating one of these re- 

 actions is to draw a strip of paper, wetted with water 

 and saturated with starch paste, through the oxidiz- 

 ing flame ; wherever the latter touches it, it becomes 

 as blue as if it had been exposed to the action of 

 electricity. In the reducing flame on the other hand 

 this coloration vanishes immediately. 



I also blew a current of air through a phosphorus 

 flame, and I got indications of the occurrence of the 

 above reactions; starch and potassium iodide in 

 particular become blue in the neighbourhood of the 

 tip of the flame. The flames of camphor and other 

 similar bodies of course resemble that of an ordinary 

 candle. The fact that in a sulphur flame such 

 oxidizing agents are not formed is explained by the 

 presence of sulphurous acid ; and in this connection 

 it is remarkable that water, upon which a sulphur 

 flame is allowed to play by means of a blow-pipe, in- 

 variably contains an appreciable quantity of sulphuric 

 acid. 



The results of my investigations therefore go to 

 show that any body, when burned in atmospheric 

 air, produces an electro-negative oxidizing substance. 

 But whether all forms of combustion give the same 



8 H A 

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( UNIVERSITY I 



