) was one of the
many kinds of machines used in the theatres of the ancients, and its
introduction was ascribed to Aeschylus. In order to represent a scene in an
interior, a movable chamber corresponding to the size of any of the three
doors was devised, which was wheeled out (ἐκκύκλημα
) or pushed out (ἐξώστρα
) (Pollux, 4.128; ἱερὸν
Aristoph. Thes. 276
; ἐκκυκλεῖται ἐπὶ τὸ ἔξω τὸ Θεσμοφόριον,
Schol. Ravenn. ibid.;
Aristoph. Ach. 375
). Donaldson thinks
was used to exhibit the
interior of an upper chamber: this would find support in the late meaning of
the word, balcony.
A special use of both machines
was to exhibit to the eyes of the spectators the results or consequences of
such acts, as murder or suicide, as could not be permitted to take place in
the proscenium, and were therefore described as having occurred behind the
An interesting illustration of the meaning of the word is to be found in
Cicero (de Prov. Cons.
6.14), who, speaking of Piso, says he
formerly concealed his vices ( “post siparium heluabatur” ),
but now practised them openly ( “jam in exostra heluatur” ).
(Donaldson, Theatre of the Greeks,
ed. 7, p. 238 ff.;
C. O. Müller, Eumen.
103, Kleine Schriften,
i. p. 524; Alb. Müller,
pp. 142-148, where there is a
full discussion of the passages where the contrivance was used.) It must be
admitted, on the whole, that the distinction between ἐξώστρα
not very clearly made out (see especially A. Müller, p. 148, n. 5).
The name exostra
was also applied to a peculiar
kind of bridge, which was thrown from a tower of the besiegers upon the
walls of a besieged town, and across which the assailants marched to attack
those of the besieged who were stationed on the ramparts to defend the town
(Veget. de Re Milit.
). This was a very old device,
frequently represented in Assyrian bas-reliefs.