With the enormous space inclosed within the solid masonry of the old Post-Office building, on the corner of Dearborn and Monroe streets, the lessees of the property start with advantages enjoyed by no other managers. The extent of the ground gives such ample measurements for the departments of a theatre that it was a necessity to plan and arrange on a scale of magnificence quite unusual. The separate divisions of the ground into stage, auditorium, and lobby are so large that only the most elaborate and colossal designs could give harmony to the whole. The Unities in construction have been regarded with perfect fidelity, and the consequence is that, vast as the building is, it appears compact and neat to an astonishing degree. The main entrance to the theatre is at the south end of the building, by means of two large doors, leading into a portico of enormous dimensions. The box-office is in the centre of the north wall of the portico, on either aide are doors leading into the orchestra and parquet circle, while on either side of a flight of stair leading up to the other circles and galleries. The arrangement of the interior is liberal indeed.