The purpose of these two cave-tigers was plain: whilst they
were in the circus, and loose, no living being could cross from one
gate to the other. They were a new and sturdy addition to the
defences of the capital. A collar of bronze was round the throat
of each, and on the collar was a massive chain which led to the
wall, where it could be payed out or hauled in by means of a
windlass in one of the hidden galleries. So that at ordinary
moments the two huge beasts could be tethered, one close to either
end of the circus, as the litter of bones and other messes showed,
leaving free passage-way between the two sets of doors.

But when I stood there by the arrow-slit, looking down into
the moonlight of the circus, these chains were slackened (though
men stood by the windlass of each), and the great striped brutes
were prowling about the circus with the links clanking and chinking
in their wake. Lying stark on the pavement were the bodies of some
eight men, dead and uneaten; and though the cave-tigers stopped
their prowlings now and again to nuzzle these, and beat them about
with playful paw-blows, they made no pretence at commencing a meal.
It was clear that this cruel sport had grown common to them, and
they knew there were other victims yet to be added to the tally.

Presently, sure enough, as I watched, a valve of the farther
gate swung back an arm's length, and a prisoner, furiously
resisting, was thrust out into the circus. He fell on his face,
and after one look around him he lay resolutely still, with eyes on
the ground passively awaiting his fate. The ponderous stone of the
gate clapped to in its place; the cave-tigers turned in their
prowlings; and a chatter of wagers ran to and fro amongst the
watchers behind the arrow-slits.