464 Prof. J. C. Maxwell on Molecules. 



It leaves him in possession of methods which nothing but scien- 

 tific work could have led him to invent ; and it places him in a 

 position from which many regions of nature, besides that which 

 he has been studying, appear under a new aspect. 



The study of molecules has developed a method of its own, 

 and it has also opened up new views of nature. 



When Lucretius wishes us to form a mental representation of 

 the motion of atoms, he tells us to look at a sunbeam shining 

 through a darkened room (the same instrument of research by 

 which Dr. Tyndall makes visible to us the dust we breathe) , and 

 to observe the motes which chase each other in all directions 

 through it. This motion of the visible motes, he tells us, is 

 but a result of the far more complicated motion of the invi- 

 sible atoms which knock the motes about. In his dream of 

 nature, as Tennyson tells us, he 



" Saw the flaring atora-strearas 

 And torrents of her myriad universe, 

 Ruining along the illimitable inane, 

 Fly on to clash together again, and make 

 Another and another frame of things 

 For ever." 



And it is no wonder that he should have attempted to burst 

 the bonds of Fate by making his atoms deviate from their 

 courses at quite uncertain times and places, thus attributing 

 to them a kind of irrational free will, which on his material- 

 istic theory is the only explanation of that power of voluntary 

 action of which we ourselves are conscious. 



As long as we have to deal with only two molecules, and 

 have all the data given us, we can calculate the result of their 

 encounter; but when we have to deal with millions of mole- 

 cules, each of which has millions of encounters in a second, the 

 complexity of the problem seems to shut out all hope of a legi- 

 timate solution. 



The modern atomists have therefore adopted a method which 

 is, I believe, new in the department of mathematical physics, 

 though it has long been in use in the section of statistics. 

 When the working members of Section F get hold of a report of 

 the census or any other document containing the numerical 

 data of economic and social science, they begin by distributing 

 the whole population into groups, according to age, income-tax, 

 education, religious belief, or criminal convictions. The number 

 of individuals is far too great to allow of their tracing the his- 

 tory of each separately ; so that, in order to reduce their labour 

 within human limits, they concentrate their attention on a small 

 number of artificial groups. The varying number of individuals 

 in each group, and not the varying state of each individual, is 

 the primary datum from which they work. 



