SOME UNSOLVED SCIENTIFIC PROBLEMS 



a special study, with the result that so-called stereo- 

 chemistry has attained a firm position. A truly amaz- 

 ing insight has been gained into the space relations of 

 the molecules of carbon compounds in particular, and 

 other compounds are under investigation. But these re- 

 sults, wonderful though they seem when the intricacy 

 of the subject is considered, are, after all, only tenta- 

 tive. It is demonstrated that some molecules have their 

 atoms arranged in perfectly definite and unalterable 

 schemes, but just how these systems are to be mechani- 

 cally pictured whether as miniature planetary systems 

 or what not remains for the investigators of the future 

 to determine. 



It appears, then, that whichever way one turns in the 

 realm of the atom and molecule, one finds it a land of 

 mysteries. In no field of science have more startling 

 discoveries been made in our century than here ; yet 

 nowhere else do there seem to lie wider realms yet un- 

 fathomed. 



in 



, LIFE PROBLEMS 



In the life history of at least one of the myriad star 

 systems there has come a time when, on the surface of 

 one of the minor members of the group, atoms of mat- 

 ter have been aggregated into such associations as to 

 constitute what is called living matter. A question 

 that at once suggests itself to any one who conceives 

 even vaguely the relative uniformity of conditions in 

 the different star groups is as to whether other worlds 

 than ours have also their complement of living forms. 

 The question has interested speculative science more 

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