IN 1925, Robert Hey tied a leather gasmask with goggles around his face and hung a satchel around his neck. He plugged an old school gas tap into the top of the satchel and connected it to the gasmask with bits of Bunsen Burner piping so that he looked like an early alien extra from Doctor Who.

The Northern Echo: Robert Hey in his aqualung in which he spent 50 minutes under the River Swale

Then the 50-year-old walked under the water of the River Swale at Billy Bank Wood, on the western edge of Richmond, and disappeared.

His story is told in a new booklet that has been produced as part of the commemorations of the 950th anniversary of Richmond castle.

Robert had been deeply touched by stories of submariners dying slow, suffocating deaths when their vessels became trapped on the seabed and, beneath Billy Bank Wood, he tried out his prototype of an aqualung that would allow them to breathe under water and escape.

He stayed submerged in the Swale, successfully breathing, for 50 minutes before concluding that his device worked.

He approached the British Admiralty, but was greeted by a wall of silence. Then he turned to French, Germans, Italians and Japanese before the Americans tested his device, and agreed that it worked. However, they took it no further.

Then, in 1929, he heard that, after lengthy trials in Scotland, the Royal Navy had adopted the Davis Submerged Escape Apparatus, invented by Robert Davis, which, he said, “was practically the same as that submitted by me in 1925”.

He became convinced that someone else was profiting from his ideas. It must have been very galling for him to learn that Robert Davis was not only awarded £25,000 for coming up with his apparatus, but he was given a knighthood and earned £15,000-a-year in royalties.

"My claim is a genuine one but, being a poor man, I cannot afford to take my case to court for it would probably be a long and costly one,” he wrote. “I am convinced that I will receive acknowledgement and some monetary reward if I can fight my case."

He built his own caravan and toured the region, holding public meetings and handing out leaflets which outlined the merits of his case. He also appealed for financial assistance to take his case further, but, unfortunately for him, none was forthcoming.

The Northern Echo: A poster in Richmondshire Museum advertising a meeting in which inventor Robert Hey would press his case over his submarine escape apparatus

A poster in Richmondshire Museum advertising a meeting in which inventor Robert Hey would press his case over his submarine escape apparatus

And Sir Robert probably had a defence that held water. He spent a lifetime creating breathing apparatus, with his first device for rescuing stricken miners developed in 1906. He then patented his first aqualung in 1910, and continued refining his diving devices practically up to his death, aged 94, in 1965.

However, he didn’t modify his aqualung for use in submarines until 1927 – two years after Robert Hey had carried out his trials in the Swale.

Despite the setback, Mr Hey did not sink without trace. He invented a device for lifting wrecked ships off the seabed, another for locating broken submarines, plus he created a cream that cured skin cancer in horses. Sadly, he could not find wider interest in any of his creations, although it is said that tobacco firm WD & HO Wills adopted his soft packaging idea by which a postage stamp sized piece of the top was ripped off allowing the cigarette to be flicked out.

It seems not to have won him many plaudits, or royalties, so disillusioned with inventing, he devoted his life to his wife, Mary, their ten children, and ornithology. He had large aviaries behind his home on The Green where he nursed forsaken fledglings back to health – until the council ordered him to release all of his birds as they were causing a nuisance.

He died in 1954, and should be considered a true great – either a great inventor who was so far ahead of his time that he was never appreciated in his day, or a great eccentric.