Have you ever wondered when the first proscenium theatre was built and what it looked like? You can get the answer to this and a number of other intriguing questions by paying a visit to the choice the exhibition that the Houghton Library has quietly put on view in its incunabula room. Entitled "The Grand Tradition in European Theatre Design," the show illustrates significant stages in the development of the stage.

The first theatre with a proscenium arch was designed in 1600 by Giovanni Battista Aleotti in Ferrara. But you will have to go to Houghton to see a handsome etching of this theatre with its five tiers of seats filled with enthusiastic playgoers.

You can also see a scale drawing of Italy's first permanent theatre, the Teatro Olimpico in vicenza, designed by Palladio in the 1580's and much copied throughout Europe. France's first theatre, of a tennis-court shape, in the Hotel de Bourgogne (1548) is also on view.

Few people realize that the attempt to construct theatres on the basis of acoustical experiments goes back at least to George Saunders designs of 1790. And those who have not yet had the thrill of visiting the Grand Opera in Paris (1861-75) can get an idea of this magnificent building and its celebrated staircase from three engraving here.

Especially impressive is the theatre designed by Victor Louis for Bordeaux in the 1770's. At the time this was the largest, most beautiful and most complex theatre anywhere in France. For purposes of comparison, there are juxtaposed the floor plans of the fourteen most famous theatres elsewhere throughout Europe.

For those interested in sets, there is a selection of prints of Baroque scenic illusions, through the air. And you can see a 1493 edition of Terence's comedies, which is the first book to contain illustrations of actual theatrical performances.

Some of the items included are recent acquisitions. All of them are worth careful inspection in their air-conditioned surroundings.