246 THE president's address. 



c 



relation with another substance which does not at the moment 

 manifest the same condition in equal degree, but which, nevertheless, 

 is capable of assuming it, we find that the second substance is 

 made to participate in the condition of the first, and becomes hot, 

 electrical, or magnetic, as the case may be. Some substances, 

 again, exposed to the influence of luminous substances in their 

 neighbourhood, become themselves luminous. As witness, for 

 example, the well-known experiment of the jDhosphorescent butterfly. 

 And again. Some substances, when brought into due relation 

 with the living tissues, become partakers of their vital condition. 

 Thus the dead food taken in becomes a living part of the living 

 body. 



But we may go a step further. If a portion of matter in any 

 one of the active conditions we are discussing comes into relation 

 with a second portion which is not capable of taking on a similar 

 condition, the influence exerted is none the less, although the 

 mode of manifestation is different. Under such circumstances 

 the condition is not simply transferred. It becomes, as it were, 

 transmuted. Thus, if a body in motion comes in contact with a 

 body at rest which is not free to move proportionately, the first 

 body is retarded or arrested, and both become heated or electrical 

 — heated especially if the two bodies are of similar nature — elec- 

 trical especially if they are of different natures. And these con- 

 ditions are developed to an extent proportionate to the resistance 

 to motion. Some substances, under such circumstances, may 

 become magnetic. Again, if matter, intensely heated, is brought 

 to bear upon a portion of matter in an oj^posite condition, the first 

 tendency is to cause motion of all the particles of this second por- 

 tion, and the phenomenon of expansion by heat takes place. But if, 

 from the nature of the particles, they cannot fly apart, or move to 

 an extent proportionate to the influence acting upon them, another 

 transmutation of condition occurs, and they become luminous. 



Again. Either directly or indirectly, chemical action or change 

 of composition, which is but an expression of molecular motion, 

 may result from, or give rise to, various transmutations of physical 

 condition. And so too, with regard to the condition which we call 

 " vital." The seed germinates, and the plant developes and grows 

 when its surroundings are in the needful physical conditions, and 

 not unless. The heated and luminous conditions of the dead mat- 

 ter around become transmuted, and add to the sum of vitality of 



