8 BIOLOGICAL LECTURES. 



Observation shows no limit to the size of a mass of matter 

 that exhibits the quality called life, and philosophically there is 

 no reason for setting any limit to the size, as one might as well 

 start with a mass the fifty-millionth of an inch in size as with 

 one the hundred-thousandth of an inch. In the absence of any 

 evidence of there being some sort of a physical and chemical 

 hiatus between those limits one is not at liberty even to 

 assume that there is, and if some of the phenomena that come 

 out from aggregates of molecules he is not able to explain 

 satisfactorily, it is safer to enlarge the possible attributes of 

 atoms themselves than to summon a genii who is wholly unac- 

 countable when off duty. But the old theory of matter was 

 that it was absolutely powerless in itself, and that the so-called 

 forces of heat, light, electricity, chemical affinity, and so on, by 

 themselves could bring nothing but disorder, and that arrange- 

 ments and adaptations required other than such agencies to 

 establish. That this is not so may easily be shown. 



Here is the solar system, an orderly body of rotating and 

 revolving globes, the orderly arrangement and motions of 

 which are believed by all astronomers to be due solely to 

 mechanical agencies, gravitation, and the laws of motion. 

 Look at a snow-flake, how beautifully symmetrical in its hexag- 

 onal geometry ! A difference in temperature of less than one 

 degree determines whether it shall remain a crystal or shall 

 lose its embodiment of form and become a minute drop of 

 water. Here again we meet with temperature that is vibra- 

 tory motion as determining not only whether a mass of matter 

 shall exist as a solid or as a fluid, but that it shall exist in a 

 symmetrical form, and not as a hodge-podge of molecules. It 

 is proper to inquire if, in order to produce such an orderly 

 arrangement of molecules it is needful to imagine some extra 

 physical agency in order to account for it. I suppose no one 

 assumes that now, even if he has no conception how the 

 phenomenon can be due to merely physical agency. Such an 

 one has enlarged his concept of the possibilities of matter and 

 is not therefore surprised at the evidences of organizations of 

 that kind. A hundred varieties of stars, or plumes, or feathers, 

 or fern forms are attributed to the properties of molecules 



