Philip Mould has The Eye.

Though, to hear him tell it, a good sense of touch and smell are equally important when it comes to spotting a masterpiece everyone else has overlooked.

In the past 15 years, Mould has rescued from obscurity five van Dycks, "three or four" Gainsboroughs, a rare portrait of King Henry VIII's oldest brother and a Romney that an unfortunate American dealer dismissed as a copy.

His forays through auction houses, estate sales and catalogues in search of "sleepers"--masterpieces that have been forgotten, hidden or cosmetically altered beyond recognition--have been so successful that the British media have dubbed Mould "the man with the golden eyes."

"I've always enjoyed hunting things down," Mould explains in a high-ceilinged office at Historical Portraits, his Mayfair gallery. "It's a physical experience. You bring all your senses to bear. You sort of dance around the painting, try and approach it from all angles."

Mould's technique is a mixture of extreme specialization--British portrait paintings from Henry VIII onward--and an eye for spotting what others miss.

He scrutinizes images for any details that might give away a hidden master--how the face is outlined, the shape of the eyebrow or whether any hairs are astray. Van Dyck, for example, often shaded the face with barely visible dark lines.

Mould also touches the work, running a finger over the image, feeling "the bumps in the paint" to judge its authenticity.

Finally, Mould relies on his instincts.

"Sometimes, when you respond to something and you're not quite sure why, it is your olfactory senses," he explains. In other words, you might be subconsciously smelling "newness" or chemicals that would indicate the work isn't as old as it appears.

After the study comes the crunch, when Mould must weigh the strength of his hunch against the financial risk of making a bid.

"Nothing brings more oxygen to the brain," he says.

The painting is taken to the restorers, where Mould must wait to hear whether he has bought a winner or a dud. The restoration process can be as simple as wiping off a layer of paint or as complicated as chipping away at years of additions.

And the wait can be excruciating.

"You get it wrong sometimes," Mould says. "If it's your own money, it just hurts. But if it is somebody else's money . . ."

British media have reported that some of his purchases have increased more than a hundredfold in value. For example, Mould bought one painting for $19,000 at auction--it later proved to be a rare royal portrait of Prince Arthur, who died in 1502. The work is now valued at around $775,000, the Times of London reported.

The House of Lords and the House of Commons have hired Mould to act as an art consultant with the aim of flushing out portraits of former politicians. The British Broadcasting Corp. put him on television to advise viewers on what to buy. And he is helping build some private collections in the United States.

His finds have been sold to the National Portrait Gallery in London, the Smithsonian Institution in Washington, and galleries throughout the world.

He says he has always been drawn to portraits and is awed by what painters can do. But it is the thrill of ferreting out something that might otherwise be overlooked that captivates him.

For Mould, it began during his school days when he collected shoe buckles--a collection of 200 that he has publicized on children's television and about which he wrote a book.

"I've always enjoyed coming across something, a scruffy-looking object in the bottom of the box, cleaning and reading up about it and re-presenting it," he says. "That is the creative side. You find something mundane and show it to be something extraordinary."