In 1955 the rate of destruction of country houses had reached its peak, at one house every five days. The fate of Avebury Manor was in serious doubt when Keiller, whose excavations of the henge had been ended by the outbreak of war in 1939, put it up for sale. Few at the time were interested in the national heritage and the prospects for the manor were bleak. At this point Sir Francis Knowles stepped in and purchased Avebury Manor from Keiller. The "Times" described Knowles as "a fundamental scientist of outstanding calibre". He immediately set about the restoration of the house which became an absorbing love as he learnt much about its construction, and claimed to have uncovered the signs of Gothic arches in the north east corner which had been filled in during Elizabethan times. The family lived partly in cottages on the estate and partly in the house over the following three years, as the works progressed with substantial financial help from the Ministry of Works.