What are dress-boxes in a theatre?

Solution 1:

Dress boxes are boxes at the level of the "dress circle" or "dress gallery." This is usually the first level above the floor of the theatre. It is the level at which audience members are most visible to other parts of the audience.

If you're going to the theatre to be seen there, rather than to watch the show, which was commonplace in the nineteenth and early twentieth centuries, the dress circle is the appropriate place to sit. People doing this would wear their best clothes, "dressing up" to improve the impression they made.

Solution 2:

Describing the "Old Vic," King Street, Bristol, Avon, Great Britain, Simon Tidworth wrote,

"The floor of the auditorium, known in France as the parterre and in England, and hereafter in this chapter, as the pit, was provided with benches and surrounded by two tiers of boxes. The nine lower, or dress, boxes, were each named after an English dramatist (Shakespeare in the middle) and held 267 people. The upper boxes were confined to the sides of the theatre, three on each side, holding 104 people, the space in the centre being left as an open gallery."

From Theatres: An Illustrated History, London, 1973 p. 121 - 122