

A KINETIC THEORY OF MATTER. 233 



give weight to any other objection to any attempt 

 to see below the surface of things than the 

 practical question : Is it likely to prove wholly 

 futile ? But now instead of imagining the 

 question : What do you mean by explaining a 

 property of matter ? to be put cynically, and 

 letting ourselves be irritated by it, suppose we 

 give to the questioner credit for being sympathetic, 

 and condescend to try and answer his question. 

 We find it not very easy to do so. All the pro- 

 perties of matter are so connected that we can 

 scarcely imagine one thoroughly explained without 

 our seeing its relation to all the others, without 

 in fact having the explanation of all, and till 

 we have this we cannot tell what we mean by 

 "explaining a property," or "explaining the 

 properties " of matter. But though this con- 

 summation may never be reached by man, the 

 progress of science may be, I believe will be, 

 step by step towards it, on many different roads 

 converging towards it from all sides. The kinetic 

 theory of gases is, as I have said, a true step 

 on one of the roads. On the very distinct road 



