220 Prof. Silliman^s Address before the 



merits to travel in ceaseless circles of organic revolution; but 

 vast numbers of them, escaping from the general ruin, are en- 

 tombed without being destroyed — their elements are not sep- 

 arated nor their members dissevered ; their forms, filled in with 

 and accurately copied by mineral matter, are encased in solid stone, 

 or frequently in metals, and thus unfold to our view — in the firm 

 rocks of our plains, hills, and mountains — a lucid record of their 

 chronology, equally incapable of being falsified or misinterpreted. 



Thus among the fossilized animals and plants, we discover 

 forms both of colossal and minute dimensions ; until the unas- 

 sisted eye ceases to distinguish between the organized being, 

 and the mineral matter by which it is enveloped. And here it 

 might well have been supposed, that we had reached the ulti- 

 mate limit of optical research ; and little did our predecessors, or 

 even ourselves, until very recently, imagine, that still another 

 world lay concealed, in senseless mineral matter, and that it 

 would in due time be fully disclosed to our inspection. Won- 

 ders on wonders had, indeed, been revealed in former years, by 

 the microscope, among the infinitesimal tribes — our living contem- 

 poraries — that at this moment, in full activity, people the bodies 

 of plants and animals, the waters, the atmosphere, and the wide 

 earth. But these are only the successors of similar races now to 

 a great extent extinct, for we are convinced by the evidence 

 of our senses, that animalcules, often of inconceivable minute- 

 ness, were not less numerous or various, in earlier ages, than at 

 present. 



The microscope, in the hands of Ehrenberg of Berlin and of 

 his pupils and followers, and of other students of microscopic 

 analysis, (among whom Professor J. W. Bailey of West Point is 

 the most distinguished in this country,) has not only passed in re- 

 view the living infusorial animalculas, but has penetrated the 

 veil that concealed the fossilized races, whose existence had not 

 been even suspected. We are now enabled to see, not vaguely, 

 but in accurate forms and with appropriate organization, the 

 thousands of millions of animalcules, which, encased in shields 

 of flint, peopled, in the dimensions of a single cubic inch, the 

 waters that deposited the polishing slate (rotten stone) of Bilin, 

 and the sediment of peat bogs ; the bog iron ores are not less re- 

 plete with similar beings, clad in ferruginous envelopes, in coats 

 of iron armor, like the knights of historical romance. Even the 



