Boring mill, Wilkinson's iron works, Bersham, nr Wrexham, Wales, 1775.
© Science Museum / Science & Society Picture Library
Model. This mill was designed by John Wilkinson (1728-1808) for boring engine cylinders and pump barrels. It was a novel arrangement and produced better results than any other boring mills of the time. Wilkinson could produce cylinders suitable for Watt's improved steam engine whereas his competitors could not. Despite common misconception this mill could not have been used for the boring of iron guns and the patent Wilkinson had for this mill made it clear that iron guns were bored using an entirely different mill.