Purchas designed St George's Presbyterian Church in Chapel Street, St Kilda (1877-80) and over 140 houses, offices, churches and cemetery buildings in Victoria between 1852 and 1909.
Several Australian architects obtained experience working in Purchas's office, including South Australian architect Edward Davies (1852-1927),[REF] while another pupil, William Black, became a senior partner in the well-known Cape Town, South Africa partnership of Black & Fagg.