Summary
Although best known as a scientific instrument maker, John Rowley extended his sphere of activity very considerably as Master of Mechanics to George I and as a hydraulic engineer at the Offices of Ordnance and Works. Re-examined and untapped sources provide fresh evidence of these aspects of his work and highlight his predilection for the arts and the virtuosity of his artefacts. The findings also have implications for studies of the instrument-making trade in the early eighteenth century.