American millionaire industrialist and art collector Armand Hammer yesterday bought the last privately owned handwritten notebook of Leonardo da Vinci for $5.2 million, a record auction price for a manuscript or book.

"There's no work of art in the world I wanted more than this," said Hammer, the 82-year-old chairman of Occedental Petroleum, who bid personally with raised finger from the front row of the crowded main auction room of Christie's here. Hammer said he had been prepared to pay much more for the 470-year-old collection of handwritten and illustrated notes by Leonardo on his scientific studies.

Hammer's winning bid was more than double the previous book or manuscript record of $2.2 million paid for a Gutenberg bible auctioned by Christie's in 1978. But it was more than $1 million less than the art auction record $6.4 million paid forthe Turner painting, "Juliet and Her Nurse," at an auction at Sotheby's in New York last summer.

It was also far less than expected by Christie's or by the seller of the Leonardo notebook, Viscount Coke, descendent of Thomas Coke, the first earl of Leicester, who had bought the notebook while traveling in Italy in 1717. Coke sold the manuscript to raise money for death taxes on his family's estate, manision and art treasures at Hilkham Hall in Norfolk in eastern England.

The potential price for the Leonardo manuscript known as the "leicester Codex," had been wildly inflated in advance speculation by the press here and in New York amidst a continuing upward spiral in art values, intense competition among major auction houses for new records, and worry among British art experts about losing the Leonardo manuscript to a foreigh buyer.

Christie's itself would not give reporters an estimate of the manuscript's value. But the auction house did little to actively discourage press speculation that it could sell for $10 million or even $20 million.

Although the bidders competing with Hammer in today's minute-and-a-half auction were not identified, there was little evidence of the prediction by Times of London, for example, that the Bibliotheque National in Paris would "go to any lengths to secure the manuscript" because it includes Leonardo's notes on the flow of water that may lie behind the water scenes in the background of his most famous painting, the "Mona Lisa," which hangs in the Louvre in Paris.

The Italian government also was expected to bid for the manuscript in an attempt to return it to Italy, but it reportedly decided to stay out of the auction because of the costs of the earthquake that has devestated southern Italy.

Hammer's interest in the Leonardo manuscript was confirmed when his presence became known as he made a winning bid of more than $90,000 for one of the Old Master paintings sold earlier in yesterday's auction. When the auctioneer announced that a still life by the French artist Chardin had been sold to "Mr. Hammer," a knowing buzz spread among the several hundred people packed into the sales room under bright television lights.

"I am a great admirer of Leonardo da Vinci," Hammer told reporters afterward. "I have one of his original two-sided drawings, and this will make a fitting addition to my collection.

Noting that the 36 pages of notes and drawings were never intended by Leonardo to be compiled into a single book, Hammer said he would separate and mount them individually between sheets of Plexiglas so that both expert scholars and ordinary museum-goers could scrutinize the nearly illegible, backwards "mirror" writing in brown ink and 360 marginal drawings that fill both sides of each folio.

The notes and illustrations were pulled together by Leonardo from other notebooks in the early 1500's, when he was in his 50's. They summarize his observations, conclusions and theories on a range of physical phenomena, with water a predominant theme.

In the manuscript's most famous passage, Leonardo anticipated the future development of submarines. After discussing safety measures for underwater swimming, including a snorkel, he declared his refusal to describe his means for remaining underwater for longer periods because " of the evil nature of men, who would use them as means of destruction at the bottom of the sea, by piercing a hole in the bottom, and sinking them with the men in them."

Hammer promised to display the manuscript in the Royal Academy of Art here. He then wants to send it around the world for exhibition before finally putting it in the Los Angeles County Museum.

But to take the manuscript out of Britan, Hammer will need an export license. It could be refused by the British government to give one of Britain's Hammer's bid. British officials refused to disclose today what they might do.

Viscount Coke had previously tried unsuccessfully to negotiate a sale of the manuscript to the government to settle the tax bill on Holkham Hall. The British Museum already has another Leonardo notebook.

Viscount Coke has pointed out that the sale of the manuscript, which has been kept locked away at Holkham Hall, will make it possible to preserve many other art treasures on display to the public at his family's magnificent Palladian mansion. It was built by the first Earl of Leicester on more than 40,000 acres in the mid-1700's to house an extraordinary collection of art and furnishings he assembled on a grand tour of the Continent.

To settle death taxes after the deaths of later earls, the Coke family already has sold or given to the government nearly 200 other rare manuscripts and books, plus about 16,000 acres of land. Agricultural income from the rest of the estate was turned into famous innovative farms in the 18th and 19th centuries, is used to maintain the mansion and its art and furniture in 18th-century splendor.