THE ANIMAL KINGDOM. 89 



furious waves, and precipitated in the form of impalpable 

 dust, also formed mountains.^ 



However extraordinary such an origin may seem, we 

 yet cannot doubt it; in fact, in certain localities we pass 

 by insensible transitions from rocks wholly composed of 

 entire shells heaped vip, to strata in which they are more 

 or less finely ground down. 



Other calcareous prominences have a still more extra- 

 ordinary origin, being formed solely of microscopic beings, 

 the extreme minuteness of which has miraculously braved 

 the destructive action of time. I am not speaking here 

 of one of those ingenious theories which science loved so 

 of old to appropriate. The microscope proves, with a 

 precision that cannot be contested, the truth of what we 

 advance. Ehrenberg has even given excellent figures of 

 all these marvels in his Geological Micrography ? 



Thus, then, when we speak metaphorically of the bones 

 of our globe, so long as the name is applied to the moun- 

 tains of coarse limestone, we are right. If it cannot be 

 looked at as the skeleton of our sphere, it can at least as 

 that of innumerable myriads which formerly peopled it. 



The geological chalk formations, which here and there 

 rise in long chains of mountains, are due to similar agglo- 

 merations of animalcules Avitli calcareous carapaces, and in 

 spite of the size of their layers, are nevertheless composed 

 entirely of the debris of microscopic Foraminifera. It is 

 they that encircle England with the immense rampart 



1 To these crushed shells, which compose the principal part of the grains of 

 calcareous strata, are joined also, as Lyell points out, the shattered remains of .-i 

 vast number of polypidoms. — Lyell's Oeol. p. 33. 



- There can be no doubt on this point. In his Oeologic/d Micrography, 

 Ehrenberg has given plates representing numerous fossils from the chalk. 

 They are so crowded together that they touch each other. Sir Ch. Lyell 

 also, in his Geology, observes that certain calcareous strata are composed of 

 small fragments of shells and coral (p. 33). 



IS 



