MANUFACTURE OF CHALK. 
(oa) 
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impassable. In due time this builder will have accomplished the 
colossal task of a causeway all around the island in its circumference 
of a hundred and eighty leagues. 
But it is more particularly in the vast Southern Ocean that these 
works are prosecuted on a grand scale by the polypes of the lime, the 
corallines, and madrepores of every kind; an animal vegetation worthy 
of comparison with the labour of the mosses in a peat-moor, which con- 
tinue to flourish in their upper growth while the lower are transformed 
and decomposed. Exactly like these vegetables, the polypes, and even 
their production, the coral, while still soft and tender, frequently become 
the nourishment of worms and fishes which feed and browse upon them 
like our eattle, derive their sustenance from them, and return them in 
the shape of chalk, without the shehtest indication of a previous exist- 
ence! Recently English seamen have discovered at the bottom of 
the sea this manufacture of chalk, which is incessantly passing from 
the living into the inorganic condition. 
But these destructive causes do not prevent the polypes from im- 
perturbably carrying on their gigantic labours, incessantly elevating the 
islands and solid barriers which are so skilfully adapted to resist the 
oceanic action. They divide the work among themselves according to 
their species. The idlest execute their share in the quiet waters, or in 
the great depths, remotest from the light; others, under the sunshine, 
among the very breakers of which they eventually become the masters. 
Soft, gelatinous, elastic, adhering to their support, the stony and 
porous mass; they deaden the fury of the boiling waters which would 
wear out the granite, and split the rock into fragments. 
Under the mild trade-winds which prevail in the tropic climates, 
the sea would uniformly flow with a tranquil tide if it did not en-- 
counter these living ramparts, which force it back upon itself, scatter 
its waves in spray, and vex it with everlasting torment. 
That the waters should assault them is their fate. But they inflict 
no injury upon them ; and in truth it is on their behalf they toil. Their 
violence does not wear them, but it wears the reef, and detaches in 
atoms the lime on which they live and with which they build. This 
lime, absorbed by them and animalized, changes into a hundred spark|- 
