550 



SCIENCE 



[N. S. Vol. XXXTV. No. 878 



for example, the well-known displacement 

 from strict periodicity of argon, cobalt and 

 tellurium all point to an unequal rate of 

 progression in isolated cases. Thus, this 

 phenomenon seems to be a general one ; the 

 various properties of material seem to os- 

 cillate with varying rhythms as the atomic 

 weights increase. The variation is so great 

 that one may almost suspect not only vary- 

 ing rhythms but also rhythms represented 

 by different types of mathematical func- 

 tions. 



These facts suggest a possible reason for 

 the great irregularity of the last part of 

 the periodic table. May it not be that the 

 nature of the elements is determined by 

 several fundamental tendencies which may 

 be compared to the Mendelian characters of 

 the modern theory of heredity? If these 

 characters recur at different intervals as 

 the atomic weight increases, a given rhythm 

 occurring at first would necessarily be ob- 

 literated toward the end of the system. 

 To change the analogy and borrow a term 

 from the nomenclature of light, we may 

 say that the tendencies which produce the 

 curves in this diagram, might first rein- 

 force and afterwards interfere with one 

 another, because they possess different 

 wave-lengths. At first, overlapping might 

 accentuate one set of properties; later the 

 changing relation might annihilate this set 

 of properties and cause another. Thus, 

 all the varieties of material may be func- 

 tions of some few fundamental character- 

 istics which progress at different rates as 

 the atomic weights increase. 



Any attempt to discover the nature of 

 these fundamental tendencies must be of a 

 highly speculative character. In our ig- 

 norance we can not distinguish between 

 cause and effect. The well-known definite 

 relations of the spectrum lines suggest that 

 at least one of the essential requirements 

 for the existence of an atom may be suscep- 



tibility to certain definite harmonic vibra- 

 tions; those compressible atoms capable of 

 vibrating in certain rhythms may be per- 

 manent, whilst other aggregations may be 

 unstable. The gap in the periodic system 

 where eA;aiodine efcacffisium should be, and 

 the amazing instability of the elements im- 

 mediately following, supports the notion. 



But here we have a cosmic puzzle for 

 future solution. To-day we lack adequate 

 data, we are blocked at every turn by our 

 ignorance; therefore, the immediate prob- 

 lem is to discover and test each step as 

 carefully as possible. "When the facts have 

 been ascertained, man will have a solid 

 basis upon which to build his future super- 

 structure of theoretical interpretation. 



The quest is not dictated by mere curi- 

 osity alone. All organic life is actuated by 

 chemical energy, and exists in a mechanism 

 and environment composed of chemical 

 substances; and the effort to understand 

 these essential conditions of human exist- 

 ence constitutes one of the most important 

 objects of human endeavor. Superficial 

 observation of the complex phenomena of 

 life can do but little; as Faraday well 

 knew, patient study of the fundamental 

 laws of the physical universe alone can help 

 to unravel the interwoven threads. Health, 

 well-being and a profound philosophic out- 

 look are alike dependent upon the result. 

 No one can predict how far we shall be 

 enabled by means of our limited intelli- 

 gence to penetrate into the mysteries of a 

 universe immeasurably vast and wonder- 

 ful; nevertheless, each step in advance is 

 certain to bring new blessing to humanity 

 and new inspiration to greater endeavor. 



Theodore William Richards 

 Harvaed Univeesity 



SCIENCE AND LITEEATUBE 

 Speech was given to man to conceal his 

 thoughts, according to some eighteenth-cen- 



