Arriving at Nuffield Place you might imagine the property had once belonged to a well-to-do family doctor or successful lawyer.

Inside, on viewing some of the threadbare carpets, it is tempting to think “well, perhaps not so well off”, with one of the main bedroom floors covered in what looks suspiciously like joined- up car mats.

But Nuffield Place once belonged to a man of fabulous wealth, who gave away £11bn in today’s money to good causes, and was at one time the world’s second largest car manufacturer after Henry Ford.

It is also a home full of treasures for anyone who wants to learn about the real William Morris, the great industrialist who arguably made a greater mark on Oxford than any other individual in history.

Now, thanks to the college that Lord Nuffield founded in Oxford, it looks like the house, which stands high on the western edge of the Chilterns, could be opened to the public as a major new tourist attraction.

The National Trust has been gifted the house by Nuffield College, with the trust to launch a campaign to raise £600,000 to put the necessary staffing and facilities in place.

Gwilym Hughes, the bursar of Nuffield College, said: “Nuffield has always been incredibly proud of its founder, whose foresight led to our being the first graduate college in Oxford and the first to admit women equally with men.

“By gifting Lord Nuffield’s home to the National Trust we will be able to share the story of this great figure with a wider public.”

Anyone who has visited Lord and Lady Nuffield’s home will know why the trust is so excited about its gift, which is not so much a house as a time capsule.

With the original furniture still in place, pictures and photographs on the wall, it is easy to imagine the car giant had just left to drive up to Cowley.

The house, at Huntercombe, near Wallingford, was built in 1914 by the Henley firm Walden and Cox for Sir John Bowring Wimble, a shipping magnate, as a country retreat.

It was sold in 1933 to Sir William Morris, who happened to be living at the time nearby in a converted golf clubhouse. (When he was raised to the peerage, he took his title from the local village and on buying Merrow Mount renamed it Nuffield Place.) Despite their considerable personal wealth, Lord Nuffield and his wife liked to live a modest lifestyle and the contents of the house are largely simple and unassuming. The property is furnished in the style of the 1930s, with reproduction furniture flower paintings and tapestry work. Some furniture is antique but most of it was custom made for Lady Nuffield by George Hughes, of the Oxford company Hallidays.

On buying the house the multi-millionaire did treat himself to a billiard room, modernised bathrooms and central heating.

Most of the clocks and rugs are of fine quality, with plenty of evidence of Lord Nuffield’s love of gadgets.

Many of Lord and Lady Nuffield’s possessions are still where they left them, offering an intimate glimpse into their worlds. Robes worn to official functions, personal letters, cartoons and gifts such as a matchbox in the shape of a car radiator and cuff links designed to look like spark plugs, can be seen throughout the house.

For Joanna Gamester, the curator for Nuffield Place, Lord Nuffield’s bedroom provides one of the most fascinating insights into his character.

The carpet is threadbare and a makeshift lamp (rigged up by the man himself) hangs over a bed, which has a blocked up fireplace as its headboard.

The curator opened a cupboard door, which instead of being full of suits, is packed with tools.

“It shows his love of mechanical things. This is where he would like to work during the night, without disturbing Lady Nuffield,” she said gesturing at the rows of spanners, screwdrivers, old clocks and a hooded torch, apparently a Second World War relic.

“You can also see that he liked to mend his own shoes,” said Ms Gamester, picking up some Phillips stick-on-soles.

Lord Nuffield’s removed appendix, pickled in a bottle, sits alongside a mechanical toy bear, while a canvas roll of tools, marked ‘Nuffield’ and stamped with an Orient Line label, shows his tools travelled with him on sea voyages to Australia, which he sometimes undertook.

It seems Lord Nuffield would often sleep in a small sunroom, which was converted from an open balcony, offering magnificent views of Wittenham Clumps.

Apparently, Lord Nuffield valued sunlight for maintaining good health.

Visitors will also be able to see an ultraviolet lamp of the type he presented to RAF nightfighter stations and to assembly-line workers in his factories during the war to compensate for deprivation of sunlight.

One of his old bathrooms now houses an iron lung, to remind visitors of Lord Nuffield’s generosity in donating such machines to numerous hospitals. In the days when polio was widespread, patients with failing breathing were placed in an iron lung, which altered the pressure on the ribcage, making the lungs inflate and deflate.

On hearing that iron lungs had saved several lives, Lord Nuffield responded by providing a machine for every hospital in the Commonwealth that asked for one.

The house has not been open in recent years, although previously, thanks to volunteers from the Friends of Nuffield Place, it did open for a few days each summer.

A National Trust spokesman said: “Our trustees have agreed to the funding for an endowment to run Nuffield Place, provided the property can begin to pay for itself as a successful attraction within five years.”

Key to its success, no doubt, will be the superb gardens surrounding the house, for the couple both loved their garden — Lady Nuffield for the flowers and Lord Nuffield for the chance to don old clothes and to potter about doing odd jobs.

With a borstal just down the road from their home, in later years Lady Nuffield, of an increasingly nervous disposition, insisted that the house’s main gate and its front door were always kept closed.

The fact that they are to be thrown open to the public for the first time will only add to her husband’s reputation as a modest but visionary man, who had a profound effect on the world far beyond both Nuffield and Oxford.