of the spine: so sudden a spring could not be the result of simple
muscular contraction, without the aid of some mechanical contrivance.
On several occasions I enjoyed some short but most pleasant excursions
in the neighbouring country. One day I went to the Botanic Garden,
where many plants, well known for their great utility, might be seen
growing. The leaves of the camphor, pepper, cinnamon, and clove trees
were delightfully aromatic; and the bread-fruit, the jaca, and the
mango, vied with each other in the magnificence of their foliage. The
landscape in the neighbourhood of Bahia almost takes its character from
the two latter trees. Before seeing them, I had no idea that any trees
could cast so black a shade on the ground. Both of them bear to the
evergreen vegetation of these climates the same kind of relation which
laurels and hollies in England do to the lighter green of the deciduous
trees. It may be observed, that the houses within the tropics are
surrounded by the most beautiful forms of vegetation, because many of
them are at the same time most useful to man. Who can doubt that these
qualities are united in the banana, the cocoa-nut, the many kinds of
palm, the orange, and the bread-fruit tree?
During this day I was particularly struck with a remark of Humboldt's,
who often alludes to "the thin vapour which, without changing the
transparency of the air, renders its tints more harmonious, and softens
its effects." This is an appearance which I have never observed in the
temperate zones. The atmosphere, seen through a short space of half or
three-quarters of a mile, was perfectly lucid, but at a greater
distance all colours were blended into a most beautiful haze, of a pale
French grey, mingled with a little blue. The condition of the
atmosphere between the morning and about noon, when the effect was most
evident, had undergone little change, excepting in its dryness. In the
interval, the difference between the dew point and temperature had
increased from 7.5 to 17 degs.
On another occasion I started early and walked to the Gavia, or topsail
mountain. The air was delightfully cool and fragrant; and the drops of
dew still glittered on the leaves of the large liliaceous plants, which
shaded the streamlets of clear water. Sitting down on a block of
granite, it was delightful to watch the various insects and birds as
they flew past. The humming-bird seems particularly fond of such shady
retired spots. Whenever I saw these little creatures buzzing round a
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