40 DEWAR ON SPONTANEOUS GENERATION. 



any sense a scientific conclusion," but we fail to see its unsoundness, 

 and if such deductions are not to be allowed, there is a limit put to 

 all scientific investigation and first causes would never be discov- 

 ered. If we thought the question worth arguing we could easily 

 show that in all sciences when direct evidence is impossible, an- 

 alogical evidence is accepted. The world will not, we think, in 

 this instance, submit to be led by an anonymous critic, even 

 although he is a contributor to Blackwood. 



The next form of force that we know of is in a plant or tree. 

 We before drew the attention of the Institute to the great similarity 

 between the force of a tree and the manner in which the tree grew, 

 to a magnet with filings at either end. We showed how there was 

 no growth comparatively speaking from the trunk, as the centre of 

 the magnet, and how the roots and branches repelled each other 

 and never came into contact ; all exactly as we find it in the iron 

 magnet.* Seeing then that there was no theory before the world 

 of the cause of the life of a plant, and seeing that all the exhibition 

 of its force could be explained by magnetism, we thought we were 

 justified in concluding that the life force of a tree was magnetism. 



TVe also spoke of an animal exhibiting somewhat similar pecu- 

 liarities in its shape and growth, to the iron magnet. A man's legs 

 and arms spread out at either end of his trunk or body, and the life 

 force or action is from the centre (or stomach where the food is 

 dissolved) to the extremities. If we take the lowest form of life — 

 the zoophyte — we find that if we cut it into innumerable pieces 

 each piece will form another complete zoophyte, thus further resem- 

 bling a magnet. The problem of the vital force of men and animals 

 not being known either, we thought ourselves justified in also 

 saying that the highest as well as the lowest development of life or 

 force was magnetism. 



Furthermore, what is true of one magnet ought to be so with 

 another. If then we are correct in saying that the molecules of an 

 iron magnet have polarity, the molecules of all plants and 

 animals being magnets, should also have polarity. Again, as 



* As in breaking a magnet also, each piece shows itself a complete magnet \ so in plants 

 or trees, each eutting shows itself also a complete magnet by growing. 



