the large domed central hall once again makes heavy use of irish stone. the romanesque arches between each column use alternating yellow and red stained blocks which sit upon bases and capitals of heavily carved portland stone. the central staircase and floors of the upper balconies are also made of portland stone. the original floor was composed of yorkstone flagstones, further portland stone, welsh ffestiniog stone, with black squares of black slate, however this floor later relaid.