ADDRESS TO THE READER. 



Geology, beyond almost every other science, offers fields 

 of research adapted to all capacities, and to every condition 

 and circumstance in life in which we may be placed. For 

 while some of its phenomena require the highest intellec- 

 tual powers, and the greatest attainments in abstract science, 

 for their successful investigation, many of its problems may 

 be solved by the most ordinary intellect, and facts replete 

 with the deepest interest may be gleaned by the most 

 casual observer. 



To the medical philosopher Geology presents peculiar 

 attractions for those hours of leisure and relaxation, which 

 are indispensable to maintain a healthy state of mind ; for 

 it requires the cultivation and application of Chemistry, 

 Botany, Comparative Anatomy, Zoology, and Physiology, — 

 sciences which form the very foundation of medical know- 

 ledge. It exerts, too, the most salutary influence, by calling 

 forth the continual exercise of our intellectual powers ; for 

 the desire to explain what is obscure in the natural records 

 of the past, induces a more accurate examination of existing 

 physical phenomena, and of the organization and habits of 



