4 On Isomeric Transtnutation^ and the Nature of 



clearly undecompounded as distinguished from indecomponihle ; 

 but, after all, that, or any other novel phrase is unnecessary, 

 for the explicit sense in which the term simple is applied by 

 the chemist, leaves the question of the bona fide simplicity of 

 the elementary bodies quite open to discussion. How fully it 

 does so, may best be gathered from the fact, that Sir H. Davy 

 and Berzelius, two of the warmest advocates of the maxim I 

 have been discussing, were the freest in speculating on the 

 nature of the elementary bodies, and the foremost in endea- 

 vouring to decompose them. 



Further, I would observe, before leaving the subject, that it 

 is not necessary, or, indeed, desirable, in the discussion of many 

 chemical problems, that the possibility of the elementary 

 bodies being simple should be considered. The study of most 

 of the properties of the suite of oxides of a metal, or of a 

 series of organic compounds, would not be facilitated, espe- 

 cially to a beginner, by shaking his faith in the stability and 

 unchangeability of their simplest components. The elemen- 

 tary bodies stand in truth, in relation to all the more complex 

 substances into whose composition they enter, like arithmeti- 

 cal ciphers, possessing in regard to all numbers higher than 

 their own a fixed value, unalterable by any discovery which 

 may be made concerning the lower figures which make up 

 them. Silicon may be a simple body, as many believe, or a 

 modification of carbon, as Dr Brown supposes, or a compound 

 of carbon, hydrogen, and oxygen, or of carbon and hydrogen, 

 as Mr Low thinks probable. But whichever of these it be, if 

 any, is as indifferent to the chemist, while ascertaining the pro- 

 portion in which it combines with oxygen to form silica, and 

 a multitude of its other relations, as it was to the builder of an 

 Egyptian pyramid, whether the bricks he made use of, so long 

 as they possessed the proper shape and weight, and coherence, 

 consisted of clay alone, or of clay mixed with sand, or of clay 

 and sand mingled with straw. 



We are free then to speculate to the uttermost on the na- 

 ture of the elementary bodies ; and if we consider from what 

 direction we are likely to obtain the means of lessening their 

 number, we shall find that the hopes of chemists («. e, of those 

 who hope at all on the matter) are fixed at present on three 



