84 MEMOIR OF DR. DALTON, AND 



ciple {vEiKog) discord, acting with it, produced the various 

 changes. We have here attraction and repulsion in their 

 early days; but it is also said by him rather curiously, 

 " discord decomposes the mixtures of the elements, and mixes 

 fire with fire, air with air, each sort of element with its like, 

 whilst concord acts on the contraries,"* as now found with 

 electric -\r and — poles. 



Leucippus first distinctly gave a meaning to the notion of 

 small particles of bodies, which he called atoms. Democritus 

 held the same opinions. Everything is composed of indivisi- 

 ble atoms. They could not be divisible, neither could they 

 be mere points. They have neither colour, taste, smell, heat, 

 nor cold : all these properties are given them by their various 

 mixtures: there are various shapes. The first impulse to 

 motion was given probably by an original force. 



This is the real meaning of all he said ; everything was 

 referred to atoms, even the soul or mind itself. This is a 

 point of great importance in the history of our knowledge of 

 matter, and one beyond which we have not yet got in 

 some of its relations. Here then we stand and are obliged 

 to review our speculations and inquiries in some respect 

 from the standing point of Leucippus and Democritus. 

 In this view we have a distinct idea attached to the com- 

 position of bodies, and although one which might have 

 readily come into the mind of any one who thought clearly on 

 the subject, yet we are not aware of the difficulties attending 

 the production of ideas, viewing them after they have been 

 overcome. Democritus arrived at the idea of distinct atoms 

 forming matter of every kind by the change of position. 

 Anaxagoras was nearly at this point, but he gave the atoms 

 characters exactly like the compound object. Democritus 

 gives the simple bodies only shape, extension, and force. 



Plato taught that the world was created by an intelligent 



• Ritter, Vol. I., p. 445. 



