OF NATURAL PHILOSOPHY. 307 



physical data, with the utmost exactness, is in itself 

 a branch of enquiry not only of the greatest im- 

 portance, but of extreme difficulty. Independent 

 of the general reasons for desiring accuracy in this 

 respect, there is one peculiar to the subject. It 

 has been suggested (by Dr. Prout), and strongly 

 insisted on (by Dr. Thomson), that all the numbers 

 representing these weights, constituting a scale of 

 great extent, in which the extremes already known 

 are in proportion to each other, as 1 to upwards of 

 200, are simple even multiples of the least of them. 

 If this be really the case, it opens views of such 

 importance as to justify any degree of labour and 

 pains in the verification of the law as a purely in- 

 ductive one. But in the actual state of chemical 

 analysis, with all deference to such high authority, 

 we confess it appears to us to stand in great need 

 of further confirmation, since it seems doubtful 

 whether such accuracy has yet been attained as to 

 enable us to answer positively for a fraction not 

 exceeding the three or four hundredth part of the 

 whole quantity to be determined : at least the re- 

 sults of the first experimenters, obtained with the 

 greatest care, differ often by a greater amount ; and 

 this degree of exactness, at least, would be required 

 to verify the law satisfactorily in the higher parts 

 of the scale. 



(342.) The mere agitation of such a question, 

 however, points out a class of phenomena in physical 

 science of a remote and singular kind, and of a very 

 high and refined order, which could never become 

 known but in an advanced state of science, not only 

 practical, but theoretical, we mean, such as con- 

 x 2 



