THE DAWN-ANIMAL AS A TEACHER IN SCIENCE. 215 



the progress of tlie earth's geological history, began, 

 as far as we know, with. Eozoon. 



Whether, then, in questioning our proto-foraminifer, 

 we have reference to the vital functions of its gelati- 

 nous sarcode, to the complexity and beauty of its 

 calcareous test, or to its capacity for effecting great 

 material results through the union of individuals, we 

 perceive that we have to do, not with a low condition 

 of those powers which we designate life, but with the 

 manifestation of those powers through the means of a 

 simple organism ; and this in a degree of perfection 

 which we, from our point of view, would have in the 

 first instance supposed impossible. 



If we imagine a world altogether destitute of life, we 

 still might have geological formations in progress. 

 Not only would volcanoes belch forth their liquid lavas 

 and their stones and ashes, but the waves and currents 

 of the ocean and the rains and streams on the land, 

 with the ceaseless decomposing action of the carbonic 

 acid of the atmosphere, would be piling up mud, sand, 

 and pebbles in the sea. There might even be some 

 formation of limestone taking place where springs 

 charged with bicarbonate of lime were oozing out on 

 the land or the bottom of the waters. But in such a 

 , world all the carbon would be in the state of carbonic 

 ^■kcid, and all the limestone would either be diffused in 

 ^Bmall quantities through various rocks or in limited 

 Hpocal beds, or in solution, perhaps as chloride of cal- 

 B^cium, in the sea. Dr. Hunt has given chemical 

 P grounds for supposing that the most ancient seas were 



