FOSSIL SPONGES, ETC. 3 



ocean of existing life ! Every fossil he picks up is 

 a letter in the great stone book ; and many such 

 letters, properly put together, have spelled out some 

 of the most wonderful generalizations of the human 

 mind. For geology as a science is peculiar in this 

 respect, that in proportion to the degree of intellec- 

 tual labour bestowed upon it, the resulting knowledge 

 is wider and broader than that afforded by any other 

 science except, perhaps, astronomy. Not only does 

 the new knowledge tell the student of other life- 

 periods beside the present, not only does it extend 

 the duration of the globe infinitely beyond the brief 

 six thousand years uneducated people still imagine 

 mark its existence, but it convinces the young student 

 beyond a doubt, that if the present living animals 

 and plants are evidences of the Creator's wisdom 

 and power, the same may be said of the extinct 

 faunas and floras of preceding epochs. Nay, when 

 he learns properly to connect their nature and dis- 

 tribution with the present, he sees that all are links 

 in the great chain of vitality, of which existing 

 animals and plants are only the continued living 

 forms ! 



The next step in the process of geological reason- 

 ing which fossils suggest, is no less interesting or 

 instructive. From seeing how many of our rocks, 

 especially limestones, are formed wholly by vital 

 agencies, the student perceives that the physical 

 geography of every past age is related to the present. 



