f it remains imprisoned, and is carried down the mountain beneath
the boiling mass; but although it cannot get free, its energy finds
vent by driving its roof of lava upwards, and so a high mound occurs in
the channel of the lava, and when in course of years the gas does find a
way out, a hollow cavern remains inside. The Grotto of Rosemont is one
of the finest-known instances of these gas-formed caverns, and, hence
its fame. Other volcanic grottoes are also found in Reunion, two of them
very fine, and many similar great hollows are found near volcanoes in
other lands, notably beneath the peak of Mount Etna in Sicily.

* * * * *

In the kingdom of Siam, about two days' journey by boat from the capital
city of Bangkok, rises a fine group of mountains, and on the highest of
these has been built a royal palace. The mountains are of volcanic
origin, and the palace actually stands on an extinct crater, which would
be very inconvenient if the slumbering fires below suddenly awakened.

In the neighbourhood of the range are the fine caverns of Petchaburg,
some of the largest existing instances of volcanic grottoes. Two are
especially grand, as the lava in cooling has twisted and twirled about
in marvellous fashion, making most wonderful effects.

The moisture coming from the roof has decorated the caverns with
splendid stalactites and stalagmites, whilst, like many other volcanic
rocks, the walls are of brilliant and harmonious colours.

The king and his people are justly proud of their caverns, and have
taken great pains that they shall be made accessible to visitors, the
ground having been levelled and staircases placed in many directions.
The largest and most beautiful cave has been turned into a temple, and
all along the sides are rows of figures. One of these is of colossal
size, and richly gilded, representing a sleeping Buddha.

THE KING OF PERSIA.

[Illustration]

Once upon a time a certain King of Persia went out hunting with all his
court. The chase that day happened to be long, and the king became very
thirsty. But no fountain or river could be found near the spot on the
plain where they rested for a short interval. At last one of the
courtiers spied a large garden not far off. It was filled with trees
bearing lemons, oranges, and grapes. His followers begged the monarch to
partake of the good things in the garden.

'Heaven forbid that I should eat anything thereof,' sa