Jan Verbruggen (1712–81)

Jan Verbruggen was a foundryman through whom important machine tool techniques were transmitted from continental Europe to England where they profoundly influenced the development of the steam engine.

Verbruggen was born in Enkhuizen, West Friesland, and trained as an artist and architect before his appointment in 1746 as Master Founder for the Admiralty of West Friesland. Within a year he began to apply techniques for boring cannon from solid castings that had been developed in Switzerland by Johann Maritz, Master Founder at Burgdorf, and transmitted by his sons to Spain and France, where they were in use at the royal foundry at Douai by the 1730s. Previously cannon had been cast as tubes, and machined to the required tolerances in vertical boring machines. Maritz made solid castings, that were rotated by water-power in horizontal machines, in which the cutters were advanced through gearing by hand wheels.

In the early 1750s Verbruggen was appointed Master Founder at the state-owned foundry at The Hague, then being re-organised after many years of neglect. He was assisted by his son, Pieter (1735-1786), newly qualified in law, and by John Siegler, who had worked for 15 years at the arsenal at Douai. Verbruggen was responsible to General de Creuznach, but in his absent in 1759 completely rebuilt the foundry which led to a decade of controversy that concluded when, with his son, he migrated to England to work at the Woolwich arsenal in 1770. He completely reorganised the cannon foundry in the next four years, and the high-quality ordnance that he produced was used on a large scale by British forces in the American War of Independence.

The technology that Verbruggen employed was surrounded in secrecy, but John Wilkinson (1728-1808), the leading British ironmaster of the time, and a manufacturer of cannon, gained knowledge of it, and patented a horizontal boring machine in 1774. He subsequently developed the machine to bore steam engine cylinders to a far higher degree of accuracy than had previously been possible. They could obviously not be bored from the solid, and in the revised machine the cylinder casting was fixed upon a supporting frame, and the revolving cutter bar passed right through it, being supported by bearings at each end. Essentially this was a new machine that might well have deserved patent protection. Wilkinson considered that it was covered by his patent of 1774, but this was revoked after being challenged by the Board of Trade in 1779, and other foundry concerns, in Britain and subsequently overseas, were free to use it. The Wilkinson boring machine was regarded by James Watt as essential in the production of cylinders for his engines. 

Jan and Pieter Verbruggen were accomplished artists, and their 50 or so water colours of operations in cannon foundries, which have been published, are amongst the most important pictorial records of 18th century industrial operations.

Jan Verbruggen played an important role in transmitting technology from the state-owned concerns of the ancien regime to the entrepreneurs of the Industrial Revolution. His 3-story brick house of 1772-3 is preserved at the Woolwich Arsenal, and his guns are displayed in military collections in Europe and North America.