Sir William Armstrong (1810 – 1900)

The Magician of the North

Tower Bridge’s original steam engines raised the bascules over 400,000 times before they were replaced in the 1970s. The technology behind this marvel of Victorian engineering was based on an invention by one of the world’s most successful industrialist-engineers, William Armstrong.

Sir William Armstrong. Copyright Cragside/National Trust

Who was William Armstrong?

William Armstrong was born on 26 November 1810 in Shieldfield, Newcastle upon Tyne. On leaving school, Armstrong followed his father’s wishes and began studying law. He went on to have a successful career, working as a solicitor for 11 years.

However, throughout this career, he remained fascinated by his childhood passion, engineering. For example, whilst on a fishing trip, Armstrong observed that waterwheels wasted much of their potential. Confident that their efficiency could be improved, he spent his spare time solving this problem.

Image: Portrait of William Armstrong by Mary Lemon Waller. Copyright Cragside/National Trust 

Illustration of Armstrong's Hydro-electric machine

Armstrong the engineer

By 1842, Armstrong had the answer. He created the world’s first hydro-electric machine, the hydraulic accumulator. These huge towers stored water at height (later, more efficient versions used weighted cylinders), allowing for users to store potential energy and access it when required. 

These accumulators were initially used to drive cranes, three of which were installed at Newcastle’s Tyne docks in 1845. This early success led Armstrong to quit the legal profession in 1846 and become a full-time engineer. 

He soon established a factory at Elswick, Newcastle, which became the centre of his rapidly growing industrial empire. For the next 50 years the company built an average of 100 cranes per year, sending them all over the world, from India to the US. They also built steam trains, many of which were exported to India. 

In 1855, they built their first bridge in Inverness, Scotland, but it wouldn’t be their last contribution to the nation’s bridges. With the hydraulic accumulator, Armstrong had invented the device that would also help raise Tower Bridge.

Image: Illustration for Le Monde Physique, Le Magnetisme et L'Electricite by Amedee Guillemin (Hachette, 1883). Credit: Look and Learn

Tower Bridge's Engine Rooms

Armstrong and Tower Bridge

Sir W G Armstrong, Mitchell & Co. Ltd, signed the contract to build and install the engines at Tower Bridge in December 1887 and were paid £85,232 (around £11.5m today). The machinery, designed in collaboration with Sir John Wolfe Barry, consisted of coal-fired boilers, steam-pumping engines, drive engine and the revolutionary accumulators.

Constructed at Elswick, the machinery was installed under the supervision of Hamilton Rendel and Samuel Homfrey, alongside John Gass, who would later become Bridge Master at Tower Bridge – you can see his photograph in the Engine Rooms. Over 300 men were involved in the project. These engines continued to power the Bridge until they were finally replaced in 1976.

Two of these engines can still be seen as part of a visit to Tower Bridge. A third engine, which was installed in 1941 is now in the Forncett Industrial Steam Museum in Norfolk.

Image: Engine Rooms at Tower Bridge

Armstrong’s other achievements

Armstrong also established successful armament and shipbuilding businesses.

In 1854, having read of the British Army’s difficulties in moving heavy field guns during the Crimean War with Russia, he invented the lighter and more mobile Armstrong Gun. Manufactured at Elswick and Woolwich Arsenal, they were exported across the globe. Armstrong presented the valuable patent for their design to the Government and was rewarded with a Knighthood from Queen Victoria.

In 1882, Armstrong Mitchell & Co was formed to specialise in warship production. Their Elswick works was the only factory in the world at the time that could build and arm a complete warship. Famously it constructed and armed the Japanese Navy, which shocked the world when it defeated the Russian Empire in 1905. Legend has it that Armstrong designed the flagship while at a party with the Japanese Emperor.

Cragside. ©National Trust Images

Armstrong also built the country house Cragside near Rothbury, Northumberland, which he designed with Richard Norman Shaw. The house is a testament to Armstrong’s engineering skills. It was the first house in the world to be lit using hydro-electricity and even had its own hydraulic lifts. 

A renowned humanist and philanthropist, Armstrong donated parks and woodlands, as well as thousands of pounds to educational and health institutions in his native Newcastle.

Sir William Armstrong died on 27 December 1900 at Cragside.

Image: Cragside. Copyright National Trust Images

Armstrong’s legacy

In 1894, Armstrong bought and restored Bamburgh Castle, ancient seat of the Kings of Northumberland, which is still owned by the family today.

Armstrong's Swing Bridge in Newcastle over the Tyne still operates using accumulators. Opened in 1876, the Swing Bridge was designed to allow large ships to pass upstream to Armstrong’s yards. The bridge still stands strong, but the shipyards and factories at Elswick are long gone.

A portrait of the great man hangs inside Tower Bridge, while his magnificent pumping engines can still be found in the nearby Engine Rooms. Here you can also look up at the huge 100-ton accumulators that powered the Bridge for over 80 years – these engineering marvels make it abundantly clear why William Armstrong was known as 'The Magician of the North'.