SOME CONSEQUENCES OF GRAHAM'S WORK 597 



constitutes molecules of helium such as we know. Apart from the 

 spontaneity with which it occurs and the fact that apparently it 

 is not subject to external influences, the decomposition of radium 

 regarded as a helide or compound of atomic helium is no more 

 remarkable than that of liquid ozone or of nitrogen chloride, 

 both of which explode under slight provocation. In these cases 

 the " source " of the energy that is liberated is clearly traceable 

 to the process whereby, in the one case, atoms of oxygen, 

 in the other, atoms of nitrogen and chlorine, become united 

 to form molecules — thus : 



20, = 20 2 + 2O ; O + O = 2 



2NC1, = 2N + 6C1 ; N + N = N 2 ; 3(C1 + CI) =* 3CL, 



After recalling how much the march of science in early 

 days was retarded by the tyranny of a theory formulated too 

 hastily and how in later times attempts have been made to 

 remedy this evil by holding the theory, provisionally only, as 

 a working hypothesis, Professor Chamberlin points out that 

 even the working hypothesis had serious disadvantages : 



11 Instinctively there is a special searching out of phenomena 

 that support it, for the mind is led by its desires. . . . From an 

 unduly favoured child it readily grows to be a master and leads 

 its author whithersoever it will. . . . Unless the theory happens 

 perchance to be the true one, all hope of the best results is 

 gone. To be sure, truth may be brought forth by an investigator 

 dominated by a false ruling idea. His very errors may indeed 

 stimulate investigation on the part of others. But the condition 

 is scarcely the less unfortunate. 



• ••*•• 



11 To avoid this grave danger the method of multiple working 

 hypotheses is urged. It differs from the simple working hypo- 

 thesis in that it distributes the effort and divides the affections. 

 ... In developing the multiple hypotheses, the effort is to bring 

 up into view every rational explanation of the phenomenon in 

 hand and to develop every tenable hypothesis as to its nature, 

 cause or origin and to give all of these as impartially as possible 

 a working form and a due place in the investigation. The 

 investigator thus becomes the parent of a family of hypotheses : 

 and by his parental relations to all is morally forbidden to fasten 

 his affections unduly upon any one. In the very nature of the 

 case, the chief danger that springs from affection is counteracted." 



If helium atoms, as I suppose, are endowed with activity in 

 an extraordinary degree, the energy developed by their union 

 in the formation of molecules may well be very, very great. 



