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Proceedings of the Royal Society 
depending like eaves, and sheltering the body of the hill from rain. 
To estimate the amount of earth per acre raised from the water-line 
of the subsoil by white ants would not in some districts he an im- 
possible task, and it would he found probably that the quantity at 
least equalled that manipulated annually in temperate regions by 
the earth-worm. 
Let me now attempt to show the way in which the work of the 
termites hears upon the natural agriculture and geology of the 
tropics. Looking at the question from the large point of view, the 
general fact to be noted is, that the soil of the tropics is in a state 
of perpetual motion. Instead of an upper crust, moistened to a 
paste by the autumn rains, and then baked hard as adamant in the 
sun ; and an under soil, hermetically sealed from the air and light, 
and inaccessible to all the natural manures derived from the de- 
composition of organic matters — these two layers being eternally 
fixed in their relation to one another — we have a slow and 
continued transference of the layers always taking place. Hot only 
to cover their depredations, but to dispose of the earth excavated 
from the underground galleries, the termites are constantly 
transporting the deeper and exhausted soils to the surface. Thus 
there is, so to speak, a constant circulation of earth in the 
tropics, a ploughing and harrowing, not furrow by furrow and 
clod by clod, hut pellet by pellet and grain by grain. Some idea 
of the extent to which the underlying earth of the tropical 
forests is thus brought to the surface will have been gathered 
from the facts already described ; hut no one who has not seen it 
with his own eyes can appreciate the gigantic magnitude of the 
process. Occasionally one sees a whole trunk or branch, and some- 
times almost an entire tree, so swathed in red mud that the bark is 
almost completely concealed, the tree looking as if it had been 
taken out bodily and dipped in some crystallising solution. It is 
not only one tree here and there that exhibits the work of the 
white ant, but in many places the whole forest is so coloured with 
dull red tunnels and patches as to give a distinct tone to the land- 
scape — an effect which, at a little distance, reminds one of the 
abend-roth in a pine forest among the Alps. Some regions are 
naturally more favourable than others to the operations of the 
termites, and to those who have only seen them at work in India, 
