256 
ISLAND LIFE. 
[part II. 
been known that these rocks are all due to the wind, which 
blows up the fine calcareous sand, the product of the disinte- 
gration of coral, shells, serpulse, and other organisms, forming 
sand-hills forty and fifty feet high, which move gradually along, 
overwhelming the lower tracts of land behind them. These 
are consolidated by the percolation of rain-water, which dissolves 
some of the lime from the more porous tracts and deposits it 
lower down, filling every fissure with stalagmite. 
The Red Clay of Bermuda . — Besides the calcareous rocks 
there is found in many parts of the islands a layer of red earth 
or clay, containing about thirty per cent, of oxide of iron. This 
very closely resembles, both in colour and chemical composition, 
the red clay of the ocean floor, found widely spread in the Atlantic 
at depths of from 2,300 to 3,150 fathoms, and occurring abund- 
antly all round Bermuda. It appears, therefore, at first sight, 
as if the ocean bed itself has been here raised to the surface, 
and a portion of its covering of red clay preserved ; and this is 
the view adopted by Mr. Jones in his paper on the “ Botany of 
Bermuda.” He says, after giving the analysis : “ This analysis 
tends to convince us that the deep chocolate-coloured red clay 
of the islands found in the lower levels, and from high-water 
mark some distance into the sea, originally came from the ocean 
floor, and that when by volcanic agency the Bermuda column was 
raised from the depths of the sea, its summit, most probably broken 
in outline, appeared above the surface covered with this red mud, 
which in the course of ages has but slightly changed its com- 
position, and yet possesses sufficient evidence to prove its identity 
with that now lying contiguous to the base of the Bermuda 
column.” But in his Guide to Bermuda Mr. Jones tells us that 
this same red earth has been found, two feet thick, under coral 
rock at a depth of forty-two feet below low-water mark, and 
that it “ rested on abed of compact calcareous sandstone.” Now* 
it is quite certain that this “ calcareous sandstone ” was never 
formed at the bottom of the deep ocean 700 miles from land ; 
and the occurrence of the red earth at different levels upon 
coralline sand rock is therefore more probably due to some process 
of decomposition of the rock itself, or of the minute organisms 
which abound in the blown sand. The forthcoming volumes on 
