only by the principal personages
of the drama. The door in the right wing was appropriated to inferior
personages, and that on the left to foreigners or persons coming from
abroad. In our plan, the five angles of the triangles not yet disposed
of determine the disposition of the scene. Opposite the centre one are
the regal doors; on each side are those by which the secondary
characters entered. Behind the scene, as in the Greek theatre, there
were apartments for the actors to retire into; and under it were
vaults or cellars, which, as in the modern stage, served for the
entrance of ghosts, or the appliance of any needful machinery. The
_proscenium_, or space between the orchestra and the scene, answering
to our stage, though deeper than the Greek, was of no great depth,
which was not required for the performance of ancient dramas, in which
only a few personages appeared on the stage at once. Besides, in the
absence of any roof, the voice of the performers would have been lost
if the stage had been too deep. That of Pompeii is only about
twenty-one feet broad, though its length is one hundred and nine.

Along the front of the stage, and between it and the orchestra, runs a
tolerably deep linear opening, the receptacle for the _aulaeum_, or
curtain, the fashion of which was just the reverse of ours, as it had
to be depressed instead of elevated when the play began. This
operation, performed by machinery of which we have no clear account,
was called _aulaeum premere_, as in the well-known line of Horace:[19]

Quatuor aut plures aulaea premuntur in horas.

It should, however, be mentioned that the ancients seem also to have
had movable scenery (_scena ductilis_), to alter the appearance of
the permanent scene when required. This must have consisted of painted
board or canvas.

Another method of illusion was by the use of masks. These were
rendered necessary by the vastness of the ancient theatres, and the
custom of performing in the open air.

In the eastern portico of the Triangular Forum are four entrances to
different parts of the greater theatre. The first two, as you enter,
lead into a large circular corridor surrounding the whole cavea; the
third opens on an area behind the scene, from which there is a
communication with the orchestra and privileged seats; the fourth led
down a long flight of steps, at the bottom of which you turn, on the
right, into the soldiers' quarter, on the left, into the area already