The arms magnate who pioneered modern artillery - as well as hydraulics and renewable energy - began his career as a solicitor.

Of all the historic artefacts in Chancery Lane, the humdrum steel lift to the Gazette's fifth-floor offices (in a distinctly workaday corner of the building) is probably the least noticed. Even my colleagues do their best to avoid it. But I treasure it as a monument to one of the Victorian age's most remarkable solicitors.  

William George Armstrong, later the first Baron Armstrong, was one of the giants of Victorian industry. He was immortalised as the arms magnate Undershaft in George Bernard Shaw's play Major Barbara. But Armstrong, who was born in 1810, began working life as a solicitor, taking articles with Newcastle practitioner Armorer Donkin and going into partnership with him in 1835. 

Armstrong's real passion was engineering, however: in particular, water power. Remarkably, Donkin seems to have indulged his junior partner's hobby of building better water wheels (or perhaps there wasn't much work on) and backed Armstrong when he went into business. 

His breakthrough invention was the hydraulic accumulator, a device for storing fluid pressure so that it can be deployed on demand as a smooth, economical and reliable motive force on demand. Thus equipped, hydraulic systems can open dock gates raise bridges or elevators and actuate the control services on an airliner.

The sudden high-pitched whine which sometimes startles passengers after a plane lands is a hydraulic pump: it may be made of exotic lightweight materials and controlled by digital electronics, but the principle is thoroughly Victorian. 

But it was with a more sinister technology that Armstrong rose to fame. After the Crimean war exposed the shortcomings of the British army's artillery, Armstrong turned his talents to building a better heavy gun. The result, a breach-loading rifled weapon firing explosive shells was a crucial step towards the industrialisation of war. Crucially and controversially, Armstrong protected his products with a raft of patents.

Controversially, because some of his innovations weren't strictly new. One newspaper quipped that he was 'adept at more than one form of rifling'.

Paradoxically, though, Armstrong was also a leading figure in the Victorian liberal campaign to abolish patents as an impediment to progress. (The 1852 Patent Law Amendment Act had created the Patent Office and with it the seeds of an intellectual property industry.) In an argument that has echoes in free market circles today, he pointed out that the overwhelming majority of patents were granted for trivial modifications, often with the object of blocking a competitor rather than protecting a great idea. 

For better or worse, the campaign failed and Armstrong, now immensely wealthy, stepped back from business and politics and occupied himself building Cragside, his Northumberland mansion which was the first building in the world to be lit by hydroelectricity. 

Even by the standards of Victorian industrialists, Armstrong was not a sympathetic character. He dealt with a walkout at his works by briskly sacking thousands of employees and replacing them with foreigners. When they realised what they had let themselves in for, they went on strike, too. 

He also seems to have suffered no qualms of conscience about exporting his weapons to all comers, including to both sides in the American civil war. 

George Bernard Shaw's cannon-maker maintains he needs no excuses for his trade. 'I am not one of those men who keep their morals and their business in watertight compartments. All the spare money my trade rivals spend on hospitals, cathedrals and other receptacles for conscience money, I devote to experiments and researches in improved methods of destroying life and property.'

Armstrong was also untroubled. He is quoted as saying: 'If I thought that war would be fomented, or the interests of humanity suffer, by what I have done, I would greatly regret it. I have no such apprehension.'

Armstrong died in 1910 so did not see the apotheosis of his big gun technology in the great war, where artillery was responsible for 58% of casualties. His memorials include Cragside and hydraulic engines in docks and lifting bridges around the country. And in the humble low-rise hydraulic lift. 

Hydraulic lifts are silent, economical and safe - no failure will send a car plummeting down the shaft. However, compared with traction elevators (the kind hauled up by ropes), they are not quick: many of my colleagues in Chancery Lane prefer the stairs. I suspect William George Armstrong didn't much like waiting around, either. 

Michael Cross is Gazette news editor