On Feb. 27, 1975, William E. Colby, then director of the Central Intelligence Agency, had an unusual telephone conversation with Parade magazine editor Lloyd Shearer. The subject was photographs Parade had obtained of a mystery ship, off the coast of Hawaii, which belonged apparently to billionaire Howard Hughes.

"We have some pictures - Summa Corp. pictures," Shearer, the editor of the weekly magazine, said, alluding to the holding company Hughes owned. The location of the ship was said to be 600 to 800 miles off Oahu.

"You are onto something very, very delicate," the director of central intelligence responded. "This one I really would like you to sit on."

Shearer was worried about his competitors in the press. "Can you turn off all the sources who have it?" he asked the CIA director. "Do you think you can sit on this?"

Colby promised: "I will try like hell."

The transcript of that telephone conversation, preserved by the CIA since it took place, concerned the Glomar Explorer, the huge salvage ship that had secretly plucked portions of a sunken Soviet submarine from the Pacific Ocean floor a few months earlier. It was a secret that the CIA was determined to keep through an intensive campaign of persuasion by Colby with some of the nation's most influential publishers, editors and broadcasters.

Details of that effort have now become public in close to 150 pages of CIA documents forced to light under the Freedom of Information Act. After contending in court for several years that Colby's efforts to suppress the Glomar Explorer story could not be disclosed without compromising national security, the CIA finally relented.

The Glomar papers obtained through the freedom of information suit tell very little about the salvage operation code-named Project Jennifer. But they provide some new insight into relationships between the government, the press, the public interest and the issue of national security.

The documents also show that the CIA effort amounted to a comprehensive domestic operation. The agency initially defended it against formal disclosure on the ground that it was carried out under the law giving the CIA authority to protect "intelligence sources and methods from unauthorized disclosure," or in short, to keep Project Jennifer a secret. The Glomar papers indicate how flexible and ambiguous those provisions can be Journalists evidently had their conversations recorded, their backgrounds investigated, their performances rated their motives questioned and discussed at length, and all of this committed to government records without their knowledged.

The censorship that the press imposed upon itself eventually crumbled in a competitive scramble. But for a time, the CIA appeared to be satisfied with its own efforts, convinced its "game plan" was working. Colby and his aides on the West Coast performed most of the chores, but at one point, Secretary of State Henry A. Kissinger was called in to impress The New York Times on the importance of being silent. Washington Post publisher Katharine Graham had already assured CIA Director Colby in a phone call some two weeks earlier in February, 1975, that "it is not anything we would like to get into." And after publishing what Colby called a "whisper" of the story, the editor of the Los Angeles Times. William F. Thomas, promised the CIA that while his reporters might keep digging Thomas would "exercise the full authority of his position to keep the results from ending up in the L.A. Times."

By Feb. 19, 1975, a CIA memorandum for the record summed up the status of the agency's efforts:

"To date, all of those in the mass media who have been briefed and cooperation solicited have honored their commitments (definitely Messrs. Seymour Hersh, Arthur Sulzberger, Bill Thomas, Jack Nelson. Mrs. Katherine (sic) Graham plus an editor on her staff and probably (deleted)."

Sulzberger is chairman and president of The New York Times and Hersh is a New York Times reporter who had been pursuing the story off and on for more than a year. Nelson is Washington bureau chief for the Los Angeles Times.

"We have committed ourselves to a game plan which to date has helped our cause," the CIA memo advised. "Let's continue."

But keeping the lid on was never viewed as a simple task. Most of the "commitments" not to publish were conditioned on everyone else's remaining silent. The CIA documents show they were worried at one point about one reporter who was described as "an average reporter, hungry but would consider the national interests above his own." On another occasion, the same reporter was variously described as an excellent and "highly accurate" writer, a "heavy drinker," and "a journalistic prostitute." In both cases, code numbers belately supplied by the agency showed the two reporters to be one and the same, someone code-named "E-14."

An agency memo also refers to "E-1," someone apparently in a high position at The New York Times, and suggests that Colby contact him and inform him of the Los Angeles Times' cooperation. With that done," . . . he will be more likely to cooperate in restraining The New York Times from printing articles on (the project)," the memo states.

"E-1" surfaces again in transcribed telephone conversation in which Colby says "I just wanted to thank you for interrupting you on Saturday."

"E-1" responds. "Don't be silly, that is my job," to which Colby replies, "Obviously you did very well, and I appreciate it."

As Shearer apparently speaking of Colby, told one CIA underling: "If he (deleted) contains it, all you guys should be given a medal of Honor."

The CIA's frenetic attempts to put the lid on the Glomar story began with a relatively brief and understated account in the Feb. 8 1975, editions of the Los Angeles Times.

The story contained few details of the submarine-raising operation, and had some essential facts wrong including the assertion that the Soviet vessel had sunk in the Atlantic instead of the Pacific Ocean.

Nonetheless, two CIA operatives went immediately to Thomas' office.

After being briefed on Glomar, Thomas said he was sorry the story had run and said he was sorry the story had run and said it would do his best to consign it to an inside page. It ended up on Page 18 in a later edition.

Thomas, the CIA representatives reported, said the story had come from four sources, and while not identifying them by name, had characterized them in general terms.

The memo said Thomas told the agents Times reporters were still working on the story, and that while "he expressed a reluctance to stop these efforts, however (he) will exercies the full authority of his position to keep the results from ending up in the L.A. Times."

At the meeting's end, the CIA said, Thomas suggested a denial of the story by the agency would be "a most appropriate action."

The unraveling of the secret began almost immediately, with a report to the CIA's Langley, Va., headquarters that a representative "is out at the airport, International Terminal, buying up as many out-of-town and foreign papers as he can get his hands on" presumably to see how widely the story had spread.

At the same time, Angus Thuermer, Colby's assistant for media matters, drafted a scenario, apparently facetious, in which Colby would explain the story to inquiring reporters.

The director, Thuermer facetiously suggested was to say that he had heard the CIA had launched an expedition to Mount Ararat to find Noah's Ark, but had no comment; another day, he was to say he heard the CIA was "tinkering around" on the ocean floor, but his position was still "no comment."

"Mr. Colby laughed and seemed entirely satisfied," the agency memo related.

Despite the frivolity of the "no comment" scenario, the CIA representatives again went to Thomas' office where the sources of the "leak" were discussed further.

Thomas, the CIA representatives reported gave his "personal assurances" the Los Angeles Times would not originate any more Glomar stories "so long as he has anything to do with the editorship of the paper."

The CIA also said that Thomas was concerned that his Washington bureau chief. Jack Nelson, had been sending to Los Angeles new reports of Glomar information gleaned in the capital, and that, "according to Thomas, Nelson now seriously questions Thomas' creditability" (sic) because the information was not being used in the newspaper.

In one CIA memo, Thomas is described as calling Nelson the "big boss in the East."

(Nelson said yesterday that he met with Colby sometime in February, 1975, and told him "there's no way you can keep the lid on this story." Colby responded that a number of publications had already agreed to cooperate, Nelson said. While recalling that he opposed Thomas' decision to hold the story but ultimately went along. Nelson denied ever telling a CIA official he questioned the editor's credibility. "I questioned the CIA's credibility, that's what I questioned," Nelson said.)

But the CIA leaders evidently felt things were beginning to go their way. In a transcribed telephone call to an unidentified person, Colby said. "The Los Angeles Times is closing it off. They were originally under the impression that (deleted). But they will cut it off as neatly as they can. I do not know whether it will work, but it deserves a college try."

While things were being buttoned up on the West Coast, Colby had one newspaper closer to home with which to deal.

On Feb. 13, he met with Katharine Graham, publisher of The Washington Post. Apparently under the impression that The Post might be on the verge of printing the Glomar story, Colby asked that it not be used.

(Mrs. Graham said yesterday that she checked with The Post's managing editor. Howard Simons, after Colby left and discovered that no one was actively working on the story. With that in mind, Mrs. Graham said. "We agreed to comply as long as the lid was on." She added that though she was uneasy about the decision then and now, "if they can prove to you that you are going to hurt your country [by publishing a story] I see nothing wrong with cooperating. And, of course, that is what, in effect, they said.")

At 6:15 that evening according to CIA transcribed notes, Mrs. Graham telephoned Coly and said. "This seems as far as we can tell, to be nothing," Colby responded: "Great."

"It is all agreed with you that it is not anything we would like to get into," Mrs Graham is reported as saying. In what appeared to be a qualification of her assurances the publishers then told Colby. "It can be that things are starting that have not gotten here."

Seemingly appreciative, Colby responded. "It is a great tribute to our journalists. You are very kind." To which Mrs. Graham reiterated, "It is totally agreed with you that it would not be anything, we have no problem with not doing it," according to the transcript.

Three minutes later, Colby called Carl Duckett, then a CIA deputy director, with the good news: "[Mrs. Graham] called and said not to worry about it, they did not know of anything but they fully agreed they would not do anything."

But, according to the transcript, the CIA director began worrying aloud about how far the agency was spreading the story in its effort to suppress publication. He told Duckett, "We are going to be in a funny position of every newsman in town knowing about it."

At his point, the CIA operatives' meetings with news executives began to reveal signs of frustration and a gnawing competitive urge.

Thomas, according to a CIA "memcom" (memo of conversation), contended that Nelson "will go along with his (Thomas') decision to suppress future reports of (Glomar)," but added that Nelson was unhappy because other papers were pursuing the story.

(Thomas said last night he had little inclination to quibble with the interpretation given to his discussions with the CIA by the agents writing the memos, adding. "There's no way I could remember all of it anyway." But he said the "gist" of his assurances to the agency during this period was that "I promised them, in effect, that I would indeed sit on the story" as long as it appeared it would compromise national security. He noted that other editors followed suit.

(In the meantime he said, he encouraged his staff to pursue the story, sending reporters to Texas and Hawaii to find new details, and assigning six or eight staffers to look at aspects in the Los Angeles area. Of the CIA references to his describing the sources of the original Times story. Thomas said that was done in the context of trying to find out from the CIA representatives what "higher sources" filtered down Glomar information to the sources the Times reporters had talked with.)

According to the documents, Thomas conveyed to the CIA the mistaken impression that The Washington Post had five reporters on the Glomar case. He also suggested to agency officials that Washington Post editors would be just as "responsive" to requests that the story be suppressed as the Los Angeles Times. He offered to assist CIA in dealing with The Post, the internal memoranda showed.

Both Thomas and Shearer expressed a strong concern that they might be scooped on the Glomar story after agreeing to withhold it.

One memorandum described Thomas as saying The New York Times had no justification for thinking the Los Angeles Times would prematurely break the story. It quoted Thomas as saying: "For Christ sakes have Abe Rosenthal call me and I'll tell him so."

Another CIA representative reported in an internal memo after meeting with Shearer at his Los Angeles home that "he [Shearer] feels every time he agrees to hold a story, he gets shafted."

Shearer, according to the memo, had agreed not to publish the Glomar story before anyone else but he demanded three weeks notification of release to accommodate his magazine's printing schedule.

Another subject of the CIA's efforts was New York Times reported Seymour Hersh. The Glomar press memos state that Hersh had been in touch with CIA officials early in 1974 to discuss Project Jennifer and was gathering details about the program which he regarded as "wasteful and perhaps ineffective."

The Monday after the Los Angeles Times story first appeared. Hersh called the CIA again with a message for Colby. The New York Timesman wanted someone from the CIA to sit down with him and, Hersh said. "I make it as good as I can. It is a positive story. Or else I am in a position of writing what I know, which is more than he thinks I know about our ladyfriend program."

Colby called Hersh in less than an hour.

"You have been first class about this thing for a long time," the CIA director told him. "You remember I came down and talked to you about it one time. You have been damn good."

Hersh replied. "It is not a question of being good. I am a citizen too."

The discussion ended on an inconclusive note. Evidently speaking of the story he might write, Hersh said, "I am going to buck it upstairs."

Any fears Colby had about the New York Times were presumably put ot rest on March 3, when the newspaper sent a formal letter to Colby agreeing to withhold the story providing it would be promptly informed if another publication planned to use it.

The letter writer, whose name was deleted, said the CIA had obtained suppression agreements from The Washington Post, the Los Angeles Times and Parade.

"Secretary Kissinger had already volunteered an oral assurance on that point," the Times letter, which was written on the stationery of the newspaper's Washington bureau, stated. The writer prefaced the message by noting that it had been composed at the request of New York Times managing editor A. M. Rosenthal.

The CIA subsequently called Shearer and Thomas about The New York Times letter, to which Thomas is said to have replied. "That's great," and Shearer is said to have said, "That's good news."

However, on March 17 in an "eyes only" message, Shearer was said to have called an agency official to say. "This thing is really travelling," and that the story was "all over" the National Press Building in Washington, D.C.

The montly journalism review, "More," had been asking a number of papers if they had killed the story and the American Civil Liberties Union was making inquiries, Shearer was quoted as saying.

"He also indicated that, from the sounds of things, he would estimate that the chances of the press holddown remaining tight are becoming less and less every day and that within the next two weeks he would expect to see the story broken," the unidentified official said of Shearer.

On March 18, the day syndicated columnist Jack Anderson broke the story on his radio show, Cloby and two assistants visited the offices of National Public Radio and CBS to solicit cooperation from their news executives. The NPR reporter who had learned about the Glomar operation was not invited to attend that meeting, a CIA memo states.

By evening, it was clear that the suppression plan was coming unstruck, and Colby advised editors of The New York Times, Washington Post and Los Angeles Times that Anderson had the story and that he was not sure Anderson would agree to withhold it. Anderson subsequently told Post Executive Editor Benjamin C. Bradlee that he was going that it would get out in a couple of days anyway.

Anderson said the CIA was trying to suppress the story "not because the operation was a secret, but because it was a $350 million failure."

He broadcast the story on the Mutual Radio Network at 9 p.m. and a second time just after 9:30 and the three newspapers immediately followed suit.

Later, the columnist and commentator reflected, that since Watergate "a lot of editors and a lot of reporters are wearing a hairshirt - sackcloth and ashes . . . and they're overdoing it a little bit, trying to prove too hard how patriotic and responsible we are."

The heavily censored CIA documents were released in connection with a U.S. District Court lawsuit brought by journalist Harriet Ann Phillippi, then a reporter for Rolling Stone magazine and now with an Atlanta television station. Her lawyer was Mark H. Lynch, an attorney for the American Civil Liberties Union and for Ralph Nader's Public Citizen Litigation Group.