MODERN VIEWS ON MATTER. 295 



Until a positive electron can be similarly isolated, the hypothesis 

 that an atom is really composed solely of electricity, that is to say, 

 of equal quantities of positive and negative electricity associated to- 

 gether in a certain grouping of little bodies, each of which is nothing 

 more than a concentrated charge of electricity of known amount, must 

 remain a hypothesis. 



7. It is a fascinating guess that the electrons constitute the funda- 

 mental substratum of which all matter is composed. That a group- 

 ing of say 700 electrons, 350 positive and 350 negative, interleaved or 

 interlocked in a state of violent motion so as to produce a stable con- 

 figuration under the influence of their centrifugal inertia and their 

 electric forces, constitutes an atom of hydrogen. That sixteen times 

 as many, in another stable grouping, constitute an atom of oxygen. 

 That some 16,000 of them go to form an atom of sodium; about 100,- 

 000 an atom of barium; and 160,000 an atom of radium. 



On this view all the elements would be regarded as different group- 

 ings of one fundamental constituent. Of all the groupings possible, 

 doubtless most are so unstable as never to be formed; but some are 

 stable, or at least relatively stable, and these stabler groupings consti- 

 tute the chemical elements that we know. The fundamental ingredient 

 of which, on this view, the whole of matter is made up, is nothing more 

 or less than electricity, in the form of an aggregate of an equal number 

 of positive and negative electric charges. 



This, when established, will be a unification of matter such as has 

 through all the ages been sought; it goes further than had been hoped, 

 for the substratum is not an unknown and hypothetical protyle, but 

 the familiar electric charge. Nevertheless, of course, it is no ultimate 

 explanation. The questions remain, what then is an electric charge? 

 what is the internal structure and constitution of an electron? 

 wherein lies the difference between positive and negative electricity? 

 and what is their relation to the ether of space? Definite questions 

 these, and doubtless some day answerable; indeed, powerful methods 

 of attack on this position have been already contrived by Dr. J. Lar- 

 mor and others; but they are questions of a higher order of difficulty 

 than those which occupy us to-day, and it must remain for a future 

 Eomanes lecturer to report progress in these directions, whenever 

 adequate progress has in fact been made. 



8. That is the end of the first half of my lecture; and six months 

 ago that, somewhat expanded, might have been the whole of it, because 

 the next portion would have seemed too fanciful; but discoveries have 

 been made, chiefly in France and in Canada — some of the most stri- 

 king of them within the present year — which remove the treatment of 

 the next part of my subject from the realm of fancy to the region 

 of probability, and justify my proceeding further with some of 



