41 JOURNAIv OF THE 



German, Lothar Meyer, that the elements are related in 

 a very remarkable way, so closely that it is possible to 

 arrang-e them all in one table, in which they form parts 

 of a system general. The law governing the variations 

 in properties of the elements is known as the Periodic 

 Law. The limits of this article will not permit any de- 

 tailed explanation of this remarkable law. The main 

 point that I wish to emphasize is, that the so-called 

 elements are shown to be related to one another and it 

 seems impossible in the lig-ht of these facts, to believe 

 that they are distinct forms of matter. It seems much 

 more probable that they are in turn composed of subtle 

 elements and it has been pointed out that all the substan- 

 ces which we now call elements, of which there are 

 about seventy, can be conceived to be made of two fun- 

 damental elements combined in different proportions. 

 There does not, however, appear to be any immediate 

 prospect of discovering these fundamental substances." 

 The Periodic System is giving us a clearer perception 

 of many things and gives promise of a deeper insight into 

 the nature of matter. Yet there are unsolved mysteries 

 connected with these numbers which the chemical world 

 has been puzzling over for nearly half-a-century. What is 

 the meaning of the group-differences and the strange recur- 

 renceof certain difference numbersand factors which were 

 noticed by Dumas and Cooke and have fascinated and be- 

 wildered a host of others since? Why should the num- 

 bers eight and eighteen be so frequently repeated in 

 these differences? Thus we find sixteen as the interval 

 between the atomic weights in the alkali, alkaline-earth, 

 oxygen and other groups (using the old designations). 

 Why should seven be the number of elements in a period? 

 Is there a great law of octaves running through nature, 

 in music, color, and the elemental simple bodies? There 

 is little of practical value to be gotten from such specu- 

 lations but judging from the large numbers of numerical 

 regularities reported it has proved a seductive field, hit- 



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