derstand each other.

It was an amusing thing to see the struggles of Blakely, who was
whipping the warriors into a fighting force. Whenever Blakely was around
the warriors would give him the military salute, as though they had been
trained up to it all their lives.

"I have often wondered where the military salute of raising the hand up
to the eyebrows comes from," said Ralph.

"Its origin dates from the commencement of the English army. During the
tournaments of the Middle Ages, after the 'Queen of Beauty' was
enthroned, the knights, who were to take part in the sports of the day,
marched past the dais upon which she sat, and, as they passed, shielded
their eyes from the rays of her beauty. Thus the habit continued, only
in a modified form, to this day."

[Illustration: _Fig. 5. The Banyan Tree._]

Uraso had charge of the advance, and when they halted that day it was
under the spreading shade of a tree that was a marvel to the boys,
although Blakely said there were plenty of them in the southern part of
the island.

This was a tree, with a large central trunk, the branches of which
spread out in all directions, to distances which were fully fifty feet
on each side, and at irregular intervals were straight stems which shot
down straight to the earth, the lower ends of which took root and thus
served as supports for the long branches.

The boys went around, examining it from all sides. "What is it?" asked
the boys.

"It is the banyan tree," answered John. "This is not the only kind which
exhibits this peculiarity. What is called the screw pine also sends down
shoots in the same way."

"Well, does each of these vertical stems become a tree of itself?"

"In the case of the mangrove these aerials, as they are called, carry up
the sap, and form leaves at their upper ends, long after the main trunk
dies."

"Do you mean that these drooping branches carry up the sap in the
opposite direction, after they take root?"

"Yes; but that is not so remarkable, when it is understood that the buds
of all trees are, in a measure, roots, and perform the same functions as
roots. The plum tree, and many others, will form roots out of the buds,
if the latter are buried in the earth."

"I have heard about the orchids, as I believe they are called. Do they
act in the same way?"

"Not altogether; there are certain plants which live on other plants and
get sustenance from them, just as some insects attach themselves to
animals