GENESIS OF THE ELEMENTS 163 



an element, and is accurately on a level with its atomic weight 

 on the vertical scale. . . . Let me suppose that at the birth of 

 the elements, as we now know them, the action of the vis genera- 

 trix might be diagrammatically represented by a journey to and 

 fro in cycles along a figure of eight path, while simultaneously 

 time is flowing on, and some circumstance by which the element- 

 forming cause is conditioned (e.g. temperature) is declining 

 (variations which I have endeavoured to represent by the down- 

 ward slope). The result of the first cycle may be represented in the 

 diagram (Fig. 55) by supposing that the unknown formative cause 

 has scattered along its journey the groupings now called hydrogen, 

 lithium, glucinum, boron, carbon, nitrogen, oxygen, fluorine, 

 sodium, magnesium, aluminium, silicon, phosphorus, sulphur, 

 and chlorine. But the swing of the pendulum is not arrested 

 at the end of the first round. It still proceeds on its journey, 

 and had the conditions remained constant, the next elementary 

 grouping generated would again be lithium, and the original 

 cycle would eternally reappear producing again and again the 

 same fourteen elements. But the conditions are not quite the 

 same. Those represented by the two mutually rectangular 

 horizontal components of the motion (say chemical and electrical 

 energy) are not materially modified ; that to which the vertical 

 component corresponds has lessened, and so, instead of lithium 

 being repeated by lithium the groupings which form the com- 

 mencement of the second cycle are not lithium but its lineal 

 descendant potassium." 1 



In this model a glance will satisfy the chemical reader that 

 the majority of the elements fall into natural order in the series 

 which fall vertically under one another. We find, for example, 

 the helium-argon-krypton group in order, with neon close by, 

 the place for xenon, 130, being vacant at the time the model 

 was designed. The triplets : 



PS Cl K Ca 



As Se Br Rb Sr 



Sb Te I Cs Ba 



1 Sir William Crookes writes to the author January 29, 1916, as follows : 

 " Since giving my account of it (the model) to the Chemical Society I have not 

 materially modified my views on the subject. But had I to make the model 

 again I should turn it iipside down, and put H at the bottom, one millim. 

 above the level of the board on which the spiral stands. Then the position 

 vertically of each element would be its atomic weight measured from the base- 

 board in millims. Uranium would then stand at the top 238 '5 ralllims. above 

 the base." 



