166 EMINENT NATURALISTS. 



study history, we obtain a more profound insight into 

 human nature, by instituting a comparison between the 



present and former states of society 



" Greology is intimately related to almost all the 

 physical sciences, as is history to the moral. An 

 historian should, if possible, be at once profoundly 

 acquainted with ethics, politics, jurisprudence, the 

 military art, theology ; in a word, with all branches of 

 knowledge whereby any insight into human affairs, or 

 into the moral and intellectual nature of man, can be 

 obtained. It would be no less desirable that a geologist 

 should be well versed in chemistry, natural philosophy, 

 mineralogy, zoology, comparative anatomy, botany — in 

 short, in every science relating to organic and inorganic 

 nature. With these accomplishments the historian and 

 geologist would rarely fail to draw correct and philoso- 

 phical conclusions from the various monuments trans- 

 mitted to them of former occurrences. They would know 

 to what combination of causes analogous effects were 

 referable, and they would often be enabled to supply 

 by inference, information concerning many events 

 unrecorded in the defective archives of former ages. 

 But the brief duration of human life, and our limited 

 powers, are so far from permitting us to aspire to such 

 extensive acquisitions, that excellence even in one 

 department is within the reach of few, and those 

 individuals most effectually promote the general 

 progress who concentrate their thoughts on a limited 

 portion of the field of inquiry. As it is necessary that 

 the historian and the cultivators of moral and political 

 science should reciprocally aid each other, so the 



