A Porton Down scientist who developed everything from chemical warfare defences to shark repellents in his work to protect the country and the Armed Forces has been given an emotional surprise to mark his 100th birthday.

Gilbert Lewis – described as a brave man who would often put himself forward for the most dangerous of missions - devoted his working life to protecting troops and civilian populations in a career spanning the Second World War through to the Cold War.

Gilbert Lewis created defences against chemical warfare

From 1940 to 1978, he played a vital role in his science specialisms with his cutting-edge work mainly in chemical warfare including developing respirators - to protect the military, the wider public and the country.

He also worked on shark repellents and dispersion involving several sea-going trials in the 1960s.

Gilbert Lewis meets younger generation of scientists at Porton Down

Today’s scientists are still using the results of that earlier research and development to provide essential defence for the modern British military.

Now, almost 40 years after his retirement, Gilbert returned to Britain’s military research base in a surprise and emotional visit arranged by his son John and staff at the Defence Science and Technology Laboratory (Dstl) at Porton Down to mark his centenary.

Gilbert Lewis saw the work of today's Dstl scientists

Gilbert, speaking of how technology had advanced since his time at the site, said: “It’s tremendously different now from when I was here – I’m amazed to see how much has changed. The work that is done now to protect the UK is incredible – there is no question about its importance.”

His son John described his father as a brave man who would often put himself forward for the most dangerous of missions and studies – all in a bid to protect the United Kingdom, its population and its Armed Forces.

Gilbert Lewis created defences against chemical attack

Research laboratory Porton Down, which nestles in more than 7,000 acres of countryside, was set up about a hundred years ago as Britain demanded a response to the horrors of the technological advances of the First World War – such as German gas attacks against British troops.

Chlorine inflicted severe chemical burns on British soldiers, many of whom died in agony, with mustard gas and phosgene soon following in the onslaughts – prompting the then secretary of state for war Lord Kitchener to call for a science and development team to examine possible defences to protect personnel.

Gilbert Lewis is introduced to Porton Man at Porton Down Dstl

Gilbert, one of Porton’s oldest surviving scientists, returned to the facility earlier this month in the week around his 100th birthday, when he met the newest Porton Down recruit, engineering apprentice Christopher King.

Gilbert, speaking of his surprise, said: “It’s unbelievable. I never expected so much fuss. I was surprised that my son John had actually approached the station, because I knew it was extremely difficult to come in here – I was really surprised and I’ve had such a marvellous time.”

Gilbert Lewis meets Christopher King at Porton Down

Mr King said: “It was a real honour to meet Gilbert and incredible to hear about the history of Dstl. I love history, engineering and science, so it’s a big deal to meet someone who’s been working on previous technology, systems and science.

“It’s also amazing to see how much technology has progressed. I only started my apprenticeship in September and who knows – my career could span as long as Gilbert’s.”

The visiting scientist was given VIP treatment, getting to see some of the most innovating parts of the Dstl site, including Porton Man, a robot mannequin that helps test the next generation of chemical and biological protective suits for the UK Armed Forces.

Many of the other scientists at Dstl were excited by the visit and keen to hear about the legacy work that Gilbert was involved in.

Colin Willis, a principal adviser in chemical protection and detection at Dstl, said: “It was an absolute pleasure to meet Gilbert and to have spoken to him, and particularly to hear some of his stories.

“We shouldn’t forget that without a lot of the research done by Gilbert and his generation we would not be able to do much of the work we do today.

“The work he did was essential and we are using the results of that to help provide better defence for the UK Armed Forces.”

Gilbert Lewis was visibly moved by the visit

Gilbert, who was visibly moved by the end of his visit, was presented with a framed certificate of appreciation for his contribution to science, as a well as a signed book about the history of Porton Down.