568 REPORT— 1886. 



ytterbium, and thulium. Didymium cannot follow in order after the triad 

 nitrogen, vanadium, columbiiim ; nor erbium follow phosphorus, arsenic, antimony; 

 iior thulium follow clilorine, bromine, iodine ; nor j'tterbium follow potassium, 

 rubidium, caesium. The inference to be drawn is that these bodies are out of 

 place, owing to their atomic weights not ha^nng been correctly determined — an 

 inference which is strengthened by the knowledge that the elementary character of 

 some of these bodies is more than doubtful, whilst the chemical attributes of most 

 of them are unknown. 



The more I study the arrangement of this zigzag curve the more I am convinced 

 that he who grasps the key will be permitted to unlock some of the deepest 

 mysteries of creation. Let us imagine if it is possible to get a glimpse of a few of 

 the secrets here hidden. Let us picture the very beginnings of time, before 

 geological ages, before the earth was thrown oft' from the central nucleus of molten 

 fluid, before even the sun himself had consolidated from the original jirotyle} 

 Let us still imagine that at this primal stage all was in an ultragaseous state, at a 

 temperature inconceivably hotter - than anything now existing in the visible 

 universe ; so high, indeed, that the chemical atoms could not yet have been 

 formed, being still far above their dissociation-point. In so far as protyle is 

 capable of radiating or reflecting light, this vast sea of incandescent mist, to an 

 astronomer in a distant star, might have appeared as a nebula, showing in the 

 spectroscope a few isolated lines, I'orecasts of hydrogen, carbon, and nitrogen 

 spectra. 



But in courss of time some process akin to cooling, probably internal, reduces 

 the temperature of the cosmic jn-oti/le to a point at which the first step in granula- 

 tion takes place ; matter, as we know it, comes into existence, and atoms are 

 formed. As soon as an atom is formed out of pr-otyle it is a store of energy, 

 potential (from its tendency to coalesce with other atoms by gravitation or 

 chemically) and kinetic (from its internal motions). To obtain this energy the 

 neighbouring protyle must be refrigerated by it,' and thereby the subsequent 

 formation of other atoms will be accelerated. But with atomic matter the 

 various forms of energy which require matter to render them evident begin to act ; 

 and, amongst others, that form of energy which has for one of its factors what we 

 now call atomic weight. Let us assume that the elementary proti/le contains within 

 itself the potentiality of every possible combining proportion or atomic weight. 

 Let it be granted that the whole of our known elements were not at this epoch 

 simultaneously created. The easiest formed element, the one most nearly allied to 

 the protyle in simplicity, is first born. Hydrogen — or shall we say helium ? — of all 

 the known elements the one of simplest structure and lowest atomic weight, is the 

 first to come into being. For some time hydrogen would be the only form of matter 

 (as we now know it) in existence, and between hydrogen and the next formed 

 element there would be a considerable gap in time, during the latter part of which 

 the element next in order of simplicity would be slowly approaching its birth- 

 point : pending this period we may suppose that the evolutionary process which 

 soon was to determine the birth of a new element would also determine its 

 atomic weight, its affinities, and its chemical position. 



' We require a word, analogous to protoplasm, to express the idea of the original 

 primal matter existing before the evolution of the chemical elements. The word I 

 have ventured to u.se for this purpose is compounded of -irpd (earlier than) and Sxtj 

 (the stuff of which things are made). The word is scarcely a new coinage, for 600 

 years ago Eoger Bacon wrote in his Dc Arte Chymiee, ' The elements are made out 

 of i/'Xi), and every element is converted into the nature of another element.' 



^ I am constrained to use words expressive of high temperature ; but I confess I 

 am unable clearly to associate with jnotyle the idea of hot or cold. Temperature, 

 radiation, and/ree coolhiy seem t3 require the periodic motions that take place in the 

 chemical atoms ; and the introduction of centres of periodic motion into protyle 

 would constitute its being .so far changed into chemical atoms. 



' I am indebted to my friend G. Johnstone Stoney, F.R.S., for the idea here put 

 forward, as well as for other valuable suggestions and criticisms on some of the 

 theoretical questions here treated of. 



I 



