020 HISTORY OF GEOLOGY. 



A new and most important instrument of palasontological investiga 

 tion has been put in the geologist's hand by Prof. Owen's discovery 

 that the internal structure of teeth, as disclosed by the microscope, is a 

 means of determining the kind of the animal. He has carried into 

 every part of the animal kingdom an examination founded upon this 

 discovery, and has published the results of this in his Odonlography , 

 As an example of the application of this character of animals, I may 

 mention that a tooth brought from Riga by Sir R. Murchison was in 

 this way ascertained by Mr. Owen to belong to a fish of the genus 

 Dendrodus. (Geology of Russia, i. 67.)] 



When it had thus been established, that the strata of the earth are 

 characterized by innumerable remains of the organized beings which 

 formerly inhabited it, and that anatomical and physiological considera- 

 tions must be carefully and skilfully applied in order rightly to inter- 

 pret these characters, the geologist and the paleontologist obviously 

 had, brought before them, many very wide and striking questions. Of 

 these we may give some instances ; but, in the first place, we may add 

 a few words concerning those eminent philosopher's to whom the 

 science owed the basis on which succeeding speculations were to be 

 built. 



Sect. 5. Intellectual Characters of the Founders of Systematic 

 Descriptive Geoloyy. 



IT would be in accordance with the course we have pursued in treating 

 of other subjects, that we should attempt to point out in the founders 

 of the science now under consideration, those intellectual qualities and 

 habits to which we ascribe their success. The very recent date of the 

 generalizations of geology, which has hardly allowed us time to distin- 

 guish the calm expression of the opinion of the wisest judges, might, 

 in this instance, relieve us from such a duty ; but since our plan 

 appears to suggest it, we will, at least, endeavor to mark the characters 

 of the founders of geology, by a few of their prominent lines. 



The three persons who must be looked upon as the main authors 

 of geological classification are, Werner, Smith, and Cuvicr. These 

 three men were of very different mental constitution; and it will, 

 perhaps, not be difficult to compare them, in reference to those qua- 

 lities which we have all along represented as the main features of the 

 discoverer's genius, clearness of ideas, the possession of numerous 

 facts, and the power of bringing these two. elements into contact. 



