The Progressive magazine's H-bomb article was brought to the attention of U.S. government officials three times before it drew a reaction, according to interviews with informed sources.

"We demanded a response," was the way one magazine source described the interplay that began in mid-February and ended up Friday with U.S. District Court Judge Robert W. Warren issuing a 10-day restraining order in Milwaukee to prevent the article's publication temporarily.

Initially, the Progressive did not intend to send the government a copy of its H-bomb article until just before publication and then "to smoke them out," according to one source.

That was changed Feb. 16 when, over protests of the magazine's editors, a draft copy was sent Washington officials by an outside party. No government officials will comment on what happened to that copy or why it triggered no Washington response on a matter that now is termed a threat to national security.

When nothing did happen, the editors themselves mailed material to Washington officials on two subsequent occasions.

Even then, it took a final call to the Department of Energy on March 1, warning that they were to go to the printer the next day before the government responded.

While lawyers, scholars and government officials weigh the First Amendment issues involved, interviews with key participants in this most recent press-government confrontation indicate less exalted factors may have been at work.

Because the matter is before the courts, those who spoke frankly the past two days about the events asked not to be quoted by name. But, pieced together from interviews and court papers, this is the chronolgy:

Early this year, freelance writer Howard Morland, who last fall had toured several government nuclear facilities on assignment for the Progressive, gave the magazine a draft article containing detailed material including sketches that he said described publicly for the first time how a thermonuclear, or H-bomb, works.

The material, according to one source, "focused on details of design. It was tough going and included six sketches that were impenetrable." It also contained a discussion of overall arms control issues, such as nuclear nonproliferation, and a history of secrecy in the atomic weapons field.

The H-bomb material, a source said, "was obviously brand new" but had to be "lightened up" by Progressive's editors and then put in "overall context" with the other material.

Among the reasons given for the need to publish the H-bomb details, the primary one was proving that "socalled secrets are not secret," as one source put it. "We knew what they had called secret was accessible... we have penetrated secrecy and what we say is now rendered credible," this source said. Another said that without knowing the details of how an H-bomb works, one could not deal with issues such as the comprehensive test ban.

It was also thought that without publishing the material, no one would believe the magazine really had it.

To make the point that they were proposing to publish what was considered secret information, a draft of the article began with an editor's note stating the "following report contains 'secret/restricted data.'"

That draft was sent to several scientists for comment and for corrections of "technical inaccuracies," one source said.

One recipient gave his copy to Massachusetts Institute of Technology Prof. George W. Rathjens. Along with his teaching Rathjens has since Jan. 2 served as deputy U.S. special representative for nonproliferation matters in the Department of State.

Rathjens has been unavailable for comment.

But a source involved in the matter said the MIT professor called the Progressive on Feb. 15 and told the editors that although he was in favor of cutting down on secrecy, he felt the article might hurt nonproliferation by helping some country develop an H-bomb capability more rapidly. He also reportedly said that publication could get Congress to pass more stringent legislation on the security issue.

The next day, Rathjens' secretary called the magazine to say the professor had decided to send the draft article to Washington for a security review.

The Progressive's editors reportedly were livid. When they finally contacted Rathjens they told him what he had done was unethical.

Thereafter, according to one source, the editors talked with their lawyers and waited for the government to act.

Five days passed and they didn't hear anything.

At that point, according to a source, the editors decided "if they [the government] were going to lower the boom it ought to be direct. They had [the manuscript] anway." The magazine felt it "should send at least some bone fides," a source said.

The most technical and supposedly secret of the materials were the sketches Morland has said he made showing where the various elements of the H-bomb should be positioned in order to get the correct, instantaneous reactions needed to create the massive explosion. A thermonuclear weapon essentially is three bombs in one. A high explosive is needed to trigger an atomic bomb which then has sufficient force to trigger the thermonuclear explosion.

The editors decided to send the sketches by registered mail to the Department of Energy's chief public information officer on nuclear matters by registered mail. To make certain it drew his attention, they put on the title, "How a Hydrogen Bomb Works." That was to be "provocative," one source said. It was sent Feb. 21.

At about that time, sources said, the Progressive editors prepared for the next issue, going to press March 2, with two covers -- one with the H-bomb article, the other on a different subject. "We had to be prepared to go either way," one person said.

Five more days passed and on Monday, Feb. 26, the magazine had still not heard anything from Washington.

The mood was one of confusion, according to sources.

"We thought maybe the material was wrong," one put it, "or that DOE couldn't care less if we printed it or not."

It was decided to call the DOE official to whom the sketches were sent and see what was going on.

Progressive managing editor Samuel H. Day Jr. made the call and found out the sketches had not arrived. "It was the snow and the Washington's Birthday holiday," a source said.

At that point, four days before material had to go to the printer, a package containing a copy of the revised Morland article and the sketches was sent air express from the magazine's office in Madison, Wis., to DOE in Washington with a letter asking for verification of "the technical accuracy of the enclosures."

It was received at DOE on the afternoon of Feb. 27 and was immediately reviewed in the department's security section.

On March 1, the day before material rial was due at the printer, the magazine editors had still not heard from Washington so they called DOE again and said they needed some answer. This time, they got it. They were told the government lawyers would be in touch with them. That same morning, the sketches sent a week earlier, arrived at DOE.

That afternoon, DOE general counsel Lynn R. Coleman called the magazine and told the editors there was material in the article that was considered classified. He suggested they negotiate but added that the government was prepared to go to court to prevent publication.

On March 2, DOE officials and government lawyers met with the magazine's editors in Madison to discuss the article.DOE Assistant Secretary for Defense Programs Duane Sewell said the government was prepared to help rewrite the article so that the secret material and sketches were deleted. He refused, however, to identify those portions that were considered classified material.

The editors said they would consider the offer and get back to Washington. They agreed not to go ahead with publication without first informing the government.

The magazine's printing was delayed over the weekend while the editors and their lawyers discussed the matter. Sometime before Tuesday, March 6, according to sources, the H-bomb ARTICLE WAS HELD BACK AND THE ALTERNATIVE COVER AND STORY WERE SENT FOR PUBLICATION IN THE Progressive's next issue.

On March 7, the Progressive's lawyer called DOE counsel Coleman and, according to Colemen's affidavit, stated "that unless the United States promptly obtained a temporary restraining order, the Progressive would proceed with publication."

Unaware the magazine had already sent its issue to press without the H-bomb article, the government moved immediately to seek an order in U.S. court.

Lawyers flew to Madison on March 8, hastily filed notice to all the participants, and delivered their proposed order to the local federal judge.

The government officials did not learn till later that the Progressive had almost a month before its next issue went to press and ample time to see what happens in court before a decision on printing the H-bomb article had to be faced again.

Meanwhile, one magazine source said, "we got a confirmation of the basic accuracy of our report."