128 ESSAYS BIOGRAPHICAL AND CHEMICAL 



may also be the case with flames. A flame, however, if 

 brought near an object containing an electric discharge 

 will discharge it; and this may possibly be due to the 

 action of electric corpuscles on the charged object. 



It will be seen, then, that we do not know yet with 

 certainty what flame is, but we are getting on the track. 

 And the direction in which to make experiments is clear. 

 Whosoever asks shall receive, but he must ask sensible 

 questions in definite order, so that the answer to the first 

 suggests a second, and the reply to the second suggests a 

 third, and so on. If that course be followed, it will 

 certainly result in discoveries, many of which may be 

 important and lead to inventions of great practical value. 

 For, indeed, an invention is often definable as a method 

 for utilising a discovery. 



