1847 the firm had an effective monopoly in the import and marketing to Europe and North America of guano from Peru as a fertilizer. This was mined by indentured Chinese labour on the Chincha Islands in conditions which the Peruvian government acknowledged in 1856 had degenerated "into a kind of Negro slave trade". The firm's profits from this trade were such that William Gibbs became the richest non-noble man in England. Throughout his life, William Gibbs and his wife Matilda Blanche Crawley-Boevey (known as Blanche), principally lived in London, for the greater part of his marriage at 16 Hyde Park Gardens, which the family owned until Blanche's death. But as he travelled regularly on business to the Port of Bristol he required a residence in the area; thus it was, in 1843, he came to buy Tyntes Place, which he subsequently renamed Tyntesfield. Within a few years of making his purchase, Gibbs began a major program of rebuilding and enlarging of the mansion. The architectural style selected for the rebuilding was a loose Gothic combining many forms and reinventions of the medieval style. The choice of Gothic was influenced by William and Blanche Gibb's Anglo-Catholic beliefs as a followers of the Oxford Movement. This wing of the Anglican Church advocated the view set out in the architect Augustus Pugin's 1836 book Contrasts, which argued for the revival of the medieval Gothic style, and "a return to the faith and the social structures of the Middle Ages". The Oxford Movement, of which both Pugin and Gibbs were disciples, later took this philosophy a step further and claimed that the Gothic style was the only architecture suitable for Christian worship. Thus it became a symbolic display of Christian beliefs and lifestyle, and was embraced by devout Victorians such as Gibbs. The completion of the mansion's chapel further accentuated the building's medieval monastical air so beloved by the Oxford Movement's devotees. When completed, the ecclesiastical design was reinforced by a dominating square tower with a steeply pitched roof adorned by four tourelles, which was demolished in 1935. Redevelopment In 1854 William Gibbs commissioned John Gregory Crace, an architect he was already using elsewhere, to redesign and decorate the principal rooms at Tyntesfield. These new designs included gilded panelling, woodwork, moulding and chimneypieces all in the Gothic style. Rebuilding work did not begin in earnest until 1863, when William Gibbs had the property substantially