Robert and Nancy Heinl wanted their book, "Written in Blood," a comprehensive history of Haiti - the world's first black republic and now on one of the world's poorest countries - published yesterday.

In voodoo, the West African religion that is synonymous with the lives and myths of Haiti, the number 22 has mystical powers.

Francois "Papa Doc" Duvalier, the tyrannical leader of the island when the Heinls lived there, became president on Sept. 22, 1957, and believed John Kennedy was killed on Nov. 22 because of Duvalier's death curse. Duvalier died on April 22, 1971, surrounded by 22 soldiers and 22 tonton macoutes, his secret police.

"The Duvalier family is now going into its 22nd year of power," says Nancy Heinl, a British-born journalist. "Our book had been so long in coming that we decided why not have a date that was important in voodoo. Be it a good or bad sign." In 1963, after four years in Haiti, the Heinls were expelled along with other Americans as Haiti began to break diplomatic relations with the U.S.

Robert Heinl, a retired Marine Corps colonel who was at Pearl Harbor and is now a reporter for The Detroit News, was the commander of U.S. military operations in Haiti from 1958 to 1963. During that time his wife became so immersed in voodoo beliefs that she accused by Duvalier of being a mambo, a voodoo priestess.

"He went to his grave convinced she was a priestess. He said it in official conversations to State Department officials," says Robert Heinl, more than a hint of pride in his soft voice.

She is still a believer, and suspects that some coincidences leading to the book's publication might reflect her beliefs.

A few months ago, the original manuscript disappeared at the printers.Then the same manuscript was stolen en route from the printer to the publisher. At the bindery, the folding machine broke when the first of 800 pages were fed into it. At the Heinls' Embassy Row home, the non-electric clocks suddenly stopped.

"Who can say if it's coincidence, spirits? Let's call it a strange coincidence," says Nancy Heinl, a petite, black-haired woman, who speaks of voodoo in solemn tones.

As she confirms the suspicious incidents - which the publisher is exploiting to promote the book - she laughs. But she becomes very nervous when describing how her husband had a stage collapse beneath him at Quantico a few months back, and then was bitten by a dog only a few days later. (The first Post reporter assigned to the Heinls' story came down with appendicitis. The second has her own voodoo doll and pins).

However, all seemed peaceful at the Heinls' yesterday, as they pointed out their Haitian art collection and the altar Nancy Heinl tends in the basement.

On the altar - actually a built-in, shelfless bookcase - are several exquisite icons, a govi jar for the spirits, a doll with one pin in it, and a paquet Congo; a bag made from an old pink ball gown of Mrs. Heinl, now filled with goat entrails. "I have always been interested in comparative religions and thought voodoo had a tremendous power," says Heinl.

In 1938 Robet Heinl, then 22, a graduate of St. Albans and Yale, went to Haiti on maneuvers and, he says "was hooked." Heinl, whose eyes are as blue as Caribbean water, recalls that "for a couple of generations of Marines at that time, Haiti was a place where we had contributed to nation-building. It was an early alliance for progress. You could see the roads built, the prisons cleaned."

But 20 years later, all that had changed. "Simply, in 1938 it worked, and by 1958 it didn't," he says. Under the elder Duvalier's repressive regime, most foreign aid was withdrawn and the middle-class fled, leaving a country of largely poor and illiterate people.

Though strong characters have dominated Haitian history, the Heinls speak particularly of "Papa Doc" Duvalier.

"In the beginning I thought he was a remarkable man. He was like an onion, layer upon layer of personality. Complex, paranoid," says the former military commander who had numerous encounters with Duvalier. "I reacted to him very respectfully - he was the president.

"He spoke below a whisper. He had the habit of making you strain, and then you wouldn't know what he said afterwards. It was hard work getting anything decisive out of him. It was like talking to a stone image."

When the couple first arrived, Nancy Heinl was invited to sit besides Duvalier at the opening of a barracks. "What I remember was this guard standing in front of me with champagne in his left hand and a 357 magnum in his right, waving it back and forth at my knee cap," she recalls, shaking her head.

As the brutality of the Duvalier regime escalated and American support was withdrawn, the Heinls said they never experienced any personal fears. "I would go to Saline, the slum of Port au Prince, to the voodoo shrines at midnight and I was never afraid," says Nancy Heinl. Only once did they have their own brush with the tonton macoutes.

Their son, Michael, was eight when they moved to Haiti, spoke flawless Creole and played with Jean-Claude Duvalier, now the country's leader. One day on a public jitney young Heinl started repeating a conversation he had heard at home concerning some peasants who had been killed. The driver was a tonton macoute and drove the bus to the police.

The boy was hauled off the palace, where "they had an interrogation room painted brown so the blood wouldn't show," according to Nancy Heinl. Young Duvalier saw his playmate and convinced the guards to release him. "We still feel grateful, and that is why we ended the book with the death of Papa Doc," she says.

For her, the island still holds some fascination, and she regrets not being allowed to return for her research.

"Haiti is a land of sounds. Even in the worst times with the bombs going off at night, the drums in the hills, the people blowing on lambi - conch shells used by the slaves to warn each other - the cries in the night, Haiti had a mystery."