character "[". ASCII character 91. Common: left square bracket; ITU-T: opening bracket; bracket. Rare: square; INTERCAL: U turn. Paired with right bracket ("]"). (1995-03-16)
The gun and the carriage, however, suffered no serious injury, though the left bracket of the latter was pierced by a splinter.
Prefixing right aligned stage directions with a left bracket was most common usage in original.