Salisbury Cathedral and Chichester Cathedral, 1402 to 1861) and fallen down; instead, Salisbury became the tallest church spire in the country on the collapse at Lincoln in 1549. The large supporting pillars at the corners of the spire are seen to bend inwards under the stress. The addition of reinforcing tie-beams above the crossing, designed by Christopher Wren in 1668, halted further deformation. The beams were hidden by a false ceiling, installed below the lantern stage of the tower. Significant changes to the cathedral were made by the architect James Wyatt in 1790, including replacement of the original rood screen and demolition
St Saviour's Cathedral, Goulburn as required, with a mass brickwork backing making up the rest of the wall. This dry press brickwork was to be laid integrally with the stonework in garden bond. The spire is yet to be completed. The spire remains an unfinished work. The Cathedral building is made of sandstone from a quarry at Marulan, except for the pillars which are of Pyrmont sandstone. The roof is natural slate. The Cathedral is unmistakably a Blacket church, on a grand scale, with nave, aisles, transepts, chancel, porches and tower. It has large and elaborate stone traceried windows and an impressive interior with