6 NATURAL HISTORY. 



verdict of the general voice. That, indeed, operates 

 surely and calmly, like the inexorable laws of Nature, 

 and consigns each bubble theory, in due time, to merited 

 forgetfulness ; but this operation may be a long one, and 

 many a theoriser, for the false excitement of temporary 

 notoriety, will risk the possession of enduring fame. 



The present age has produced many of those pseudo- 

 naturalists, though not so many as that immediately 

 preceding it. The spirit is not extinct ; and therefore 

 it is that I would caution my younger fellow-students, 

 for whom these pages are written, against allowing their 

 imaginations to be carried away by specious theories, or 

 any theories which do not proceed from a deep study 

 of Nature. Much more would I caution them against 

 building systems of their own. Their place clearly is, 

 to learn and not to teach, and until they have brought 

 together a very considerable amount of observations they 

 can scarcely have an adequate conception of what a sys- 

 tem should be. In heaping together these observations, 

 they will find real pleasure, and will become, as they 

 proceed, more and more sensible of the capacity of 

 mind and knowledge which is required in him who shall 

 venture to sketch out a " Systema Naturae" Let not 

 man boast, like the irreverent monument to Buffon, of 

 having "a mind equal to the majesty of Nature ;" and 

 let none of us act as if we laid claim to such a mind. 

 The portion of the created universe with which the 

 naturalist occupies himself is indeed small, if we com- 

 pare our world with the stellar system, and estimate its 

 value by the line and the plummet ; but, the more we 

 become conversant with its heights and depths, the more 



