s filled full of the tempting liquid. On tasting it we
found it sweet, and of a not unpleasant flavour, and wonderfully like
milk.

We returned to the boat with our prize. Domingos had meantime been
boiling some coffee; as we had now no sugar, the fresh milk proved a
most valuable acquisition. The Indians, however, recommended us not to
take much of it. We kept it, intending to use it again in the evening,
but on taking off the lid of one of the monkey-cups, we found that our
milk had thickened into a stiff and excessively tenacious glue. "My cow
good?" asked Duppo, as he saw us tasting the liquid. When we showed him
the gluey substance in the evening, he inquired sagaciously whether the
milk of our cow would keep so long, and we confessed that, in that
climate, it would be very likely to turn sour. After this, on several
occasions we obtained fresh milk from the cow-tree for our breakfasts
and suppers.

We encamped at night on a bank, and found two sorts of tiger-beetles,
with very large heads, running about on the sand. It was extraordinary
how rapidly they moved. Arthur and I tried to catch them, but each time
they baffled us. One was very similar in hue to the sand over which it
runs, the other was of a brilliant copper colour. Arthur, who was very
acute in his remarks, observed that the white species ran far more
swiftly than the copper-coloured one. As they only appear in the gloom
or night, the white is far more easily seen than the darker one; and
this has by the Creator greater means afforded it of escaping from its
enemies. The dark-coloured one, however, he discovered, is not left
without means of defence; for when at last Duppo caught one for him, he
found that on touching it it emitted a strong, peculiar, and offensive
putrid odour, which is not the case with the whiter one.

"How delightful it is!" he exclaimed, "to examine the habits of God's
creatures, and see how admirably adapted they are to the life they are
destined to lead."

I must not, however, attempt to describe the numberless insects and
creatures of all sorts we met with on our voyage. Duppo brought us a
large wood-cricket, called the _Tanana_, the wonderfully loud and not
unmusical notes of which we had often heard. These sounds, we found,
were produced by the overlapping edges of the wing-cases, which they rub
together. In each wing-case the inner edge, near the lower part, has a
horny expansion. On one wing this horny e