NEW GROUND. 
205 
them as a protection, whereas the mere resources 
of craft or duplicity will only disappoint and 
destroy. 
Madagascar lies in a region of the earth that 
is almost entirely within the influence of the 
south-east trades-wind set of the atmosphere for 
at least a considerable portion of the year. Nor 
is this the only source whence the constant land 
breezes which sweep over the island are derived. 
For a considerable period every year the sun¬ 
shine falls upon the great land terraces and 
slopes with a force which rapidly heats the air, 
which expands as it heats, till the thin air is 
driven backward by the stronger and heavier 
atmosphere which is constantly rising and flow¬ 
ing inland from the comparatively cool surface 
of the Indian Ocean. This deduction is a matter 
of scientific observation, and not a mere hypo¬ 
thetical statement; and it has been established, 
from exact data taken on the east coast, that the 
winds blow inward from the sea very much more 
frequently than out to the sea. The proportion 
is about three times to once. Now, when this sea- 
wind comes in upon Madagascar from the broad 
sweep of the Indian Ocean, it is necessarily laden 
with pretty nearly as much vapour as it can 
carry. With this burden it rushes along the 
land, and, as it rushes, it also glides up the ter¬ 
races which have already been described. It then 
