Association of American Geologists and Naturalists. 221 



hard agates and chalcedonies, the opals, the jaspers, and the chalk 

 flints, bear ample testimony, by their included organic forms, that 

 the time was, when they were not in existence, and these evan- 

 escent beings, the fossil animalculae, enjoyed their day or hour of 

 life, before these beautiful minerals were formed. 



In the same manner, the vast beds of tertiary, of chalk, and 

 many of the secondary limestones disclose, under the searching 

 scrutiny of the microscope, a world of minute organic forms, that 

 once lived in that earlier ocean by whose waves their elegant 

 structures were first sustained, and then broken down and com- 

 minuted into an earthy calcareous powder, which, to the naked 

 eye, appears almost impalpable. In similar circumstances, both 

 in the cretaceous and tertiary strata of New Jersey and Virginia, 

 (as observed by Professors Bailey and Rogers,) the microscope 

 reveals to our eyes myriads of Foraminifera* or polythalamous 

 shells — their divisions perfect, their delicate edges and processes 

 in fine preservation, their porcelain varnish lustrous and beautiful, 

 and still so inconceivably small, that thousands of them have been 

 seen to run, in a few minutes, through a pin-hole in a piece of 

 paper.f 



The attention of geologists is now powerfully directed to the 

 results of microscopic analysis, which will probably be carried 

 back through the earlier aqueous rocks, and may not cease until 

 we arrive within the domain of fire, nor perhaps even before 

 we reach to rocks that have been in actual fusion, where, of 

 course, we should expect that all traces of organization would 

 be destroyed. Although we cannot assign a limit to these re- 

 searches, we are certain that one must exist, since, it is obvious, 

 that mineral matter must have been first in the order of the cre- 

 ation ; for no organized beings could have existed, until earth, 

 waters, and air were provided, as the scene of their action, and 

 to afford them the elements of nutrition. 



It appears from these instances, that geology takes a high 

 rank among the physical sciences. Indeed, while to a great ex- 

 tent it involves a knowledge of them all, it repays the zealous 

 explorer with a rich intellectual recompense, and affords to civili- 



* This Jour., Vol xli, p. 213. Prof. H. D. Rogers's final report on New Jersey. 

 Prof. W. B. Rogers's report on geology of Virginia, 1841, pp. 38 to 42. 



t This latter fact was observed by Mr. Lonsdale with respect to the chalk of 

 England. 



