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CHAPTER X. 
FOSSIL FORAMINIFERA—MICROSCOPICAL EXAMINATION OF CHALK AND 
FLINT. 
‘Where is the dust that has not been alive?” 
Youne. 
Tuat those infinitesimal forms of animal existence which 
swarm throughout the waters of the ocean, but whose pre- 
sence can only be made manifest by the aid of the microscope, 
are preserved in a fossil state,—that their durable remains 
constitute mountain ranges, and form the subsoil of exten- 
sive regions,—and that the most stupendous monuments 
erected by man are constructed of the petrified relics of 
beings invisible to the unassisted eye,—are facts not the 
least astounding of those which modern Geology has revealed. 
This interesting field of research, which the labours of that 
eminent observer M. Ehrenberg first made known, has since — 
been explored by other naturalists, and in every part of the 
world many of the Tertiary and Secondary deposits have been 
found to contain microscopic organisms in profusion. At pre- 
sent this branch of paleeontology is in its infancy, and it offers 
to the young student an inexhaustible and most attractive 
path of scientific investigation ; it possesses, too, this great 
advantage over many others, that it can be pursued at home, 
and the materials for its prosecution are everywhere at hand. 
Unlike my explorations in the Wealden, in which a few 
fragments of bones, or teeth, scattered at wide intervals 
through the rocks, and in localities many miles apart, were 
