This historic place was registered under the Historic Places Act 1980. This report includes the text from the original Building Classification Committee report considered by the NZHPT Board at the time of registration. In 1859 the property at Charteris Bay was purchased by the Reverend R R Bradley. He farmed the property until his death in 1892, when It was taken over by his son, R Orton Bradley. He contributed greatly to the technological development of the property and on his death bequeathed it to the nation as a 'National Park'. It failed to meet the criteria for this status, but a special public status was provided for by the R O Bradley Estate Act 1972. The millhouse, with its under-shot wheel powered by water brought from further up the valley, is the technological hub of the farm property. The belt driven machinery in the mill, or machine shop, includes a milling saw, lathe, and a generator to produce electricity. The millhouse was not a successful commercial venture, most of the timber cut there being for private or local use. The generators installed in 1901 and 1922 provided the electric power for one of-the earliest electrical lighting systems on Banks Peninsula.