statue are sculptures of caryatids. The Small Concert Room designed by Charles Robert Cockerell and completed in 1856, is elliptical measuring 72 by 77 feet, when built it had a capacity for 1,100 people, the stage is 30 by 12 feet, and is lavishly decorated. In the past it was known as the Golden Concert Room. A balcony supported by caryatids runs round the room. At the back of the platform are attached columns, decorated with arabesques, supporting a frieze with griffins and between the columns are mirrors. The concert room was refurbished between 2000 and 2007. This included making alterations to comply with the Disability Discrimination Act, restoring the historical painting scheme and restoring the chandelier, which consists of 2,824 crystal pieces. It has seating for an audience of 480. Ventilation and heating of the building In the basement is part of a unique heating and ventilation system devised by Dr Boswell Reid. This was the first attempt at providing air conditioning in a public building in the United Kingdom, its aim being to warm and ventilate the building without draughts. Air drawn in via two shafts at either end of the eastern portico was warmed by five hot water pipes, that were heated by two coke-fired boilers and two steam boilers, these latter two were only used in extremely cold weather. The air was circulated by four fans wide driven by a 10 horsepower steam engine. In hot weather the air was cooled using cold mains water, small fountains in the air shafts cooling the incoming air. The air from the system entered the Great Hall via grilles at the back of the sculpture niches and in the risers of the seating tiers in the Small Concert Hall, stale air was drawn out through grilles in the ceilings. The air flow was controlled by a large number of workers opening and closing a series of canvas flaps via ropes and pulleys, though the court rooms had valves beneath the benches that could be controlled by the occupants. The system treated different parts of the building as zones allowing separate heating. In 2005 the Heritage Group of the Chartered Institution of Building Services Engineers awarded its first Blue Plaque to St George's Hall recognising it as the World's First Air Conditioned Building. Assizes Until 1984 the Liverpool Assizes (later the Crown Court) were held in the courtroom at the