OF NATURAL PHILOSOPHY 79 



structed, and appear precisely as it stood at their 

 conclusion. To take another instance : mineralogy, 

 till modern times, could hardly be said to exist. 

 The description of even the precious stones in 

 Theophrastus and Pliny are, in most cases, hardly 

 sufficient to identify them, and in many fall short 

 even of that humble object ; more recent observers, 

 by attending more carefully to the obvious cha- 

 racters of minerals, had formed a pretty extensive 

 catalogue of them, and made various attempts to 

 arrange and methodize the knowledge thus ac- 

 quired, and even to deduce some general conclu- 

 sions respecting the forms they habitually assume : 

 but from the moment that chemical analysis was 

 applied to resolve them into their constituent ele- 

 ments, and that, led by a happy accident, the 

 genius of Bergmann discovered the general fact, that 

 they could be cloven or split in such directions as 

 to lay bare their peculiar primitive or fundamental 

 forms, (which lay concealed within them, as the 

 statue might be conceived encrusted in its marble 

 envelope,) from that moment, mineralogy ceased 

 to be an unmeaning list of names, a mere laborious 

 cataloguing of stones and rubbish, and became, 

 what it now is, a regular, methodical, and most 

 important science, in which every year is bringing 

 to light new relations, new laws, and new practical 

 applications. 



(68.) Experience once recognized as the fountain 

 of all our knowledge of nature, it follows that, in the 

 study of nature and its laws, we ought at once to 

 make up our minds to dismiss as idle prejudices, or 

 at least suspend as premature, any preconceived 



