The new £50 bank note, which features pioneering Birmingham industrialists Matthew Boulton and James Watt, has now entered circulation.

Birmingham-born manufacturer Boulton, and Watt, a visionary engineer, spearheaded the Industrial Revolution in Britain in the 18th century by producing the world’s first steam engines.

They were also influential members of the Lunar Society, a group of intellectuals which formed and met in Birmingham.

Bank of England governor Mervyn King said: “The Bank is delighted to acknowledge the invaluable contribution Boulton and Watt made to the advancement of engineering by featuring them on the new £50 banknote.

“The partnership of an innovator and an entrepreneur created exactly the kind of commercial success that we will need in this country as we rebalance our economy over the years ahead.”

It’s the first Bank of England note to carry two portraits and the signature of Chris Salmon, appointed the Bank’s chief cashier in April.

The notes will eventually replace the current £50 banknote featuring Sir John Houblon and boast enhanced security features to help the public and traders identify genuine currency and to guard against counterfeit production.