"Time marches on, a lawyer for Westinghouse Electric Corp. said at one point in a federal court in Richmond a week ago while recounting the history of some disputed uranium supply contracts eight utilities are seeking to enforce.

Slowly, Judge Robert Merhige Jr. interjected, glancing at the clock.

But the clock keeping time on the complicated Westinghouse uranium trial ran "just" six months, and Merhige was one day away from the end of closing arguments.

In contrast, the clock keeping time on the trial of the government's civil antitrust case charging International Business Machines Corp. with attempting to monopolize the computer business has been ticking for more than three years, and it may be only half over: IBM has just begun presenting its defense. While IBM counsel have estimated their case could take a year, their estimates may well be as wrong as the government's estimates of the length of time its case would take.

The mounting statistics on the case - brought on the last business day of the Johnson administration in 1969 after three years of investigation - are staggering already. At the third anniversary ofthe trial last month, there already had been 489 trial days producing more than 72,000 pages - a transcript which, lined up, would take up 28 feet of shelf space. Fifty-three witnesses had testified in the courtroom, one of them for 78 days spread over 10 months. Direct testimony and cross-examination of the witnesses took up 47,000 pages. Another 69 witnesses testified by deposition. The offering of documents and depositions - 4,900 exhibits were offered into evidence, 4,700 accepted - took up 125 court days and 21,000 pages of transcript.

As "slowly" as judge Merhige thought the next-to-the-last day of the Westinghouse trial day was moving, to an observer, the procedings moved along briskly, efficiently, and cheerfully - as has the entire trial. The pace has been achieved despite the long hours the judge schedules (eight in the morning to six at night is an average day), the complex issues raisd and the complications generated by 10 separate plaintiffs - with lawyers for each - presenting their often quite different cases in a combined trial.

And it moved especially quickly compared to the IBM trial. A recent visit to the courtroom in New York gives meaning to the ever-mounting statistics. The atmosphere is court in New York is dreary and dull; the trial drags. The relatively short court day of just over four hours - which the lawyers say is typical - seemed interminable. Testimony and questions drone on. Is it any wonder an IBM public relations specialist who began monitoring the trial every day at first gave it up "to avoid brain damage?" Richard case, an IBM executive and the company's first witness in its defense, was already testifying for the 17th day. No sense of urgency or efficiency characterizes the trial.

The length, the massiveness, the complexity and the dreariness of the case cause some to worry that "IBM" is giving antitrust cases, particularly the government's antitrust cases, a bad reputation. "It doesn't take much antitrust sense - just common sense - to see that there is something wrong with antitrust enforcement when major cases take decades to complete," Sen. Edward Kennedy (D-Mass.), chairman of the Senate Antitrust and Monopoly Subcommittee, told the Computer & Communications Industry Association, a group of companies that has a big stake in the outcome of the case.

Some worry about the effect on private enforcement of the antitrust laws as well; a vast majority of all antitrust actions are filed by private individuals and companies, not the government.

"The case could have a disastrous effect . . . if people begin feeling that antitrust cases are unmanageable, overwhelming and not capable of being tried," a lawyer associated with the case says. "Whether the government is right or IBM is right about the issues, the case does a great disservice to the cause of justice.

"The government has made some serious charges about the leading company in a major industry, if it's right, there ought to have been some relief already," he says. "If IBM is right, the case has done a disservice to the industry. Either way, it's a shame that it's taken so long.

There is, almost everyone agrees, enough blame to touch everyone involved for this seemingly unending case.

For its part, the government is blamed for lagging in its prosecution in the early stages, for failing to focus and streamline its case, causing it to dump massive amounts of evidence into the record, and for a high turnover in staff contributing to an inability to manage the case as effectively as it might have with a continous team.

For its part, IBM is blamed for trying - and succeeding - in delaying and obstructing the case. If the computer giant loses the case and is found to have attempted to monopolize the manufacture and marketing of computers, if faces potential divesituture, so it has no real incentive to hurry along, antitrust lawyers suggest. "No matter how much good will they can be said to have, there is just simply no reason for a defendant in this case ever to get to the end of the trial." John Shenfield, assistant attorney general for antitrust, told the Senate antitrust subcommittee when pressed about the case.

Finally, and most importantly, however, lawyers associated with the case and other judicial observers blame United States District Judge David Edelstein, the chief judge in the Southern District of New York and the sole arbiter of the case.

"I think there are a lot of reason for the length of the case, but the judge has to bear the principal responsibility, his job is to make sure the case gets tried in a reasonable period of time," says Maxwell Blecher, a plaintiff antitrust lawyer who recently was named to the Presidential Antitrust Reveiw Commission to study how to expedite big cases.

Blecher notes that the judge let the case go to trial without an agreed upon statement of the issues that would have narrowed the questions on which evidence would be presented.

Given what he calls the government's traditional tendency to overtry cases by putting into evidence whatever it has turned up - no matter how marginal itsusefulness or how cumulative - Blecher says a strong and controlling judge should have limited the duplicative and background material he said went into the record. When IBM, "as most defendants would do," effectively delayed the case by taking an enoemous period of time to cross examine witnesses - half the amount of time the government's witnesses spent on the stand was taken up by IBM's cross-examination - the judge could and should have stepped in and put some restrictions on the lawyers, according to Blecher.

A lawyer associated with the case agrees."Both sides could have done more to expedite the case, but the fundamental problem is with the judge," he says. "When you think back, there was not a single thing or decision that went wrong, but a pattern where the judge . . . didn't force the parties to limit what they were doing.

"A practicing lawyer is not supposed to be objective; he pursues his own interests; so when the judge doesn't exercise some control, the trial runs amok," he says.

The lawyer cited two examples. IBM served massive document demands on the federal government during the discovery period, asking for what amounts to 30 million pieces of paper. "Under the federal rules of civil procedure, they have the right to do that, and they found a lot of documents that were useful," he said. "But in the overall interest of judicial administration, the benefit of opening up the government files to that extent doesn't justify the time and expense."

The same thing is true of the government's recent request to take depositions of more than 100 witnesses IBM plans to use in its case. No one disputes that the government ought to have a chance to depose the witnesses who were newly added to IBM's list, but questions have been raised about the need to question who had been deposed before. The government contends that new depositions are needed to aid in cross-examination because of new documents and changed events since the start of the trial.

"From the government's stand point, it makes sense," the lawyer says. "But the return for that massive effort probably doesn't justify it, and probably ought to be limited by the judge."

In the first three years of trial, the Justice Department had offered a massive number of documents and extensive testimony on a number of IBM practices it contends show IBM's intent to monopolize the market, and use of that power to stifle its competitors. One, for instance, is the now-discontinued practice of "bumbling," quoting a price for the whole system rather than pricing pieces separately, a practice the government says kept computer companies that couldn't produce a whole system from competing effectively with IBM.

Another challenged practice was IBM's lease orientation in marketing its products, which the government says gives IBM the first crack at upgrading its customers' equipment and keeps potential entrasts out because they would need massive amounts of capital and the ability to wait for a recovery on their investment.

The government also ought to show that IBM prematurely announced the introduction of computer products - it calls this portion of the case "fighting machines" - in markets where competition threatened, long before they were marketable or had been tested, in order to keep customers from going to competitors' products.

In its defense, IBM is hoping to show that its practices are those of a successful entrepreneur in a competitive business world keeping one step ahead of the pack, and that its products are bought by so many because they are of higher quality.

The case already has dragged on so long that many of the IBM officials responsible for the challenged practices have left the company or died, and most of the computer products whose histories are being explored in such depth and detail are already technologically obsolete. Also, most of the government lawyers who started on the case and many of IBM's lawyers have moved on to different things.