APPENDIX A LI 



Dr. George "Wilson, brother of the late Sir Daniel Wilson, of 

 Toronto University, in his essay on Boyle, published about the middle at 

 tlie last century, remarks that there is no à priori objection to the possi- 

 bilit}^ of transmutation as there is to the possibility of a self-sustaining 

 perpetual motion. " It may be realized any day " he says. 



It has been partially realized to-day, to the extent, that is, that na- 

 ture has been discovered working transformations of some of the chemical 

 elements, and science is now eagerly inquiring to how many elements the 

 process extends. But no one has yet learned to imitate the powers of 

 nature in this respect, 



Greek Atomic Theory. 



As consequences of these discoveries, two erroneous opinions have got 

 abroad; one, of a vague popular character, that a fatal defect has been 

 ifound in the basis of chemistry; the other, more definite, that the old 

 Atomic Theory has been disestablished, and the death-knell of the Atom 

 rung. A slight sketch may show that these opinions have no sufficient 

 foundation. 



j It may* occur to any one who has noticed a stone ground to powder 

 or a drop of water subdivided to the cover of a pin-point, to inquire how 

 far the subdivision can be carried. The question is not limited to what 

 can be seen by the naked eye, or detected by the most powerful micro- 

 scope but extends beyond the region of sight to what can be inferred by 

 sound reasoning from careful observations. 



It is, as jSTewton put it, and as Lord Kelvin re-states it, not a 

 question whether we can imagine the subdivision to go on for ever, but 

 a practical question, whether, using the forces of Nature at our com- 

 mand, we come eventually to an end of subdivision, and have something 

 indivisible, an atom. No one has ever seen an atom, and from the 

 nature of light itself, there is no hope that we shall ever invent an 

 instrument which will enable us to see it. Still we may safely infer 

 the existence of atoms even though a procession of ciphers headed by 

 unity, giving the numl^er that would extend over the twenty-fifth part 

 of an inch, should not help the imagination much to picture their 

 smallness. 



Sir John Hersehel asserts that the idea of the atom is an absolute 

 necessity of the " thinking mind, and is of all ages and nations." 



Whewell in his " History of Scientific Ideas " says: — " The doctrine 

 " that matter consists of minute, simple, indivisiljle, indestructible 

 " particles as its ultimate elements has been current in all ages and all 

 " countries wherever the tendency of man to wide and subtle speculation 

 " has been active.^' 



