1894] The British Association President's Address. 131 



Recent Ideas of Matter. 



In 1904 (a century later) the modern i ieas as to the atomic 



and molecular composition of matter, the kinetic theory ot g^ases, 



the laws of the i onservation and dissipation of energy, so potent in 



19th century science, have been surpassed by the latest affirmation 



that gross matter is, after all, a mere appearance, whose physica' 



basis is electricity. 



Electrical Monads, 



The chemist's uliimate atoms, whose groupings constitute the 

 molecules of the chemic.il elements ate now regarded as them- 

 selves groups of sub-atoms or monads. These are not electrified 

 panicles of matter ; but are electricity itself. The different 

 elements of the chemist ;ire really different arrangements and 

 motions of monads. " Thus " said Mr. Balfour, "two centuries 

 ago electricity seemed but a scientific toy. It is by many declared 

 to-day to constitute the reality, of which matter is but the sensible 

 expression." 



Qualities of Matter. 



Formerly matter was said to have primary, essential qualities, 

 such as shape and mass, which existed independent of any obser- 

 ver. It had also secondary qualities, like warmth and colour, 

 which had no existence excepting as effects upon the organs of 

 sense-perception in living beings. Mass is now pronounced to be 

 no longer an attribute or a quality, but a relation. Far from 

 being necessary and unchangeable, as was formerly thought, mass 

 changes with every change in velocity, and especially at high rates 

 of velocity. Professor Rutherford states that these corpuseles 

 have a velocity in some cases 40,000 times greater than a rifle 

 bullet which travels at the rnte of about ^ a mile per second. 

 {Harper's Mag., Jan., 1904 ) 



Feeblest Forms of Force Chiefly Apparent. 



Chemical affinity, molecular cohesion and the like, hitherto so 

 important in the eyes of the physicist, are mere residual effects, 

 the feebler manifestations of force as compared with the inense 

 electrical forces which keep the atom in being. Gravitation, New- 

 ton's imposing discovery, is trifling compared with the attractions 

 and repulsions of electrically charged bodies, while these, again, 



