118 MR, H. WILDE ON THE 



IX, On the Origin of Elementartj Substances, and on some 

 new Relations of their Atomic Weights. By Henry 

 WiLDE^ Esq. 



Bead April 30th, 1878. 



The hypothesis that the solar system_, as at present con- 

 stituted, was formed by the successive condensations of a 

 gaseous substance rotating under the influence of a 

 central force, has so much evidence in its favour that it 

 may be affirmed to equal the best of that obtained from 

 the geological record of the changes which in past times 

 have taken place on the surface of the terrestrial globe. 

 That this gaseous or primordial substance consisted of a 

 chaotic mixture of the 65 elements known to chemists is a 

 notion too absurd to be entertained by any one possessing 

 the faculty of philosophic thinking, as the regular 

 gradation of properties observable in certain groups of 

 elements clearly shows that elementary species are not 

 eternal, but have a history, which it is the proper object 

 of physical science to unfold. 



One of the principal facts which, to my mind, establishes 

 the nebular theory of the formation of planetary systems 

 on a firm basis, is Bode's empirical law of the distances 

 of the members of the solar system from each other and 

 from the central body, as in this law is comprehended the 

 idea of nebular condensation in definite proportions. 

 Now, if elementary species were created from a homo- 

 geneous substance possessing a capacity for change in 

 definite proportions, it is probable that the greater number 

 of elements would be formed during, or after, the transition 



