When the last big legislative trains are steamed up and ready to leave the station, as they were yesterday on Capitol Hill, there's always someone out on the platform trying to throw on a last few pieces of luggage.

The closing hours of any congressional session are the moment of the end-game specialists, those lawmakers who are adept at using the pressure points of time and must-pass legislation to their advantage. It is also the time when the congressional leadership must be constantly on alert for contraband.

Yesterday was no exception as the House and Senate moved toward enactment of some of the most important legislation of the 101st Congress: a $490 billion deficit-reduction plan that includes comprehensive child care legislation, and a total overhaul of the Clean Air Act.

Though the annual rush to adjournment usually involves the House and Senate furiously completing key business, this year's logjam was more impressive than most. Rarely has the success or failure of a Congress been more on the line in the final day or two than it was for this Congress heading into the weekend.

In addition to the huge budget bill and the clean air rewrite, Congress was struggling to complete action on a major housing bill, an important immigration measure and legislation setting defense spending policy for the next year. It also had to deal with a rash of annual appropriations bills, as well as a crime-fighting measure on which House and Senate negotiators dropped proposals to expand the list of federal crimes subject to the death penalty, curb assault weapons, restrict death-row appeals and allow illegally seized evidence to be admitted in court under some circumstances

With those huge and complicated bills on the line, as well as dozens of other less significant measures hanging in the balance as Congress pushed for adjournment, the halls and back rooms of the Capitol yesterday took on the look of an oriental bazaar. Across Capitol Hill, deals were being cut, trades were being made and last-minute negotiations were being conducted.

House Budget Committee chairman Leon E. Panetta (D-Calif.), for example, set up shop in the first floor Capitol office of Majority Leader Richard A. Gephardt (D-Mo.) and spent much of his day trying to keep extraneous provisions out of the huge budget bill.

Around 1:30 p.m., Panetta managed to jettison -- he said he hoped for the last time -- a provision to redesign U.S. coins that Sen. Alan Cranston (D-Calif.) and House Banking Committee Chairman Henry B. Gonzalez (D-Tex.) have been furiously throwing aboard every legislative vehicle they could find this week.

On Thursday, the proposal to redesign the reverse sides -- the sides opposite the profiles of U.S. presidents -- of the penny, nickel, dime, quarter and half-dollar was tossed off an omnibus housing bill. But by late the same night, it had miraculously clambored aboard the deficit-reduction bill, courtesy of Cranston.

The coin idea is opposed by the Treasury but has been pushed by a recent social companion of Cranston's, Diane Wolf, 36, a New York socialite and daughter of a wealthy Texas oil man who was appointed to a term on the Commission on Fine Arts in 1985.

Also nixed was a special tax break for a small slice of the insurance industry sought by Senate Majority Leader George J. Mitchell (D-Maine). The provision would have given a favorable rate to firms that sell one type of disability insurance, including a company located in Portland in Mitchell's home state.

Also dropped was a provision sought by Sen. Daniel Patrick Moynihan (D-N.Y.) to permit the wealthy to deduct the full value of works of art donated to museums.

Congressional aides monitoring the progress of the huge deficit-reduction bill -- which will run thousands of pages -- were nervously predicting that this year they might avoid the usual embarrassing stories about last-minute special interest provisions being slipped into the legislation.

"I talked to joint tax, and they said there were no rifle shots in this one," said one staffer referring to Congress's Joint Committee on Taxation and using Capitol Hill argot for a legislative provision narrowly targeted toward a specific company or industry. "Democracy is breaking out all over -- even in this place."

Nonetheless, the deficit-reduction legislation includes about $2.5 billion in energy tax breaks over five years and a $200 million tax break for ethanol production, the benefits of which will accure primarily to Archer-Daniels-Midland Co., a huge agribusiness firm and one of Washington's most adroit political players.

Hoping to discover more such examples of hidden legislative maneuvering, Rep. Curt Weldon (R-Pa.) yesterday offered a reward -- lunch at the Monocle restaurant -- to anyone who could point him in the direction of "special interest windfalls."

As with the end of any congressional session, time was a valuable ally to those with special pleadings.

Yesterday morning, members of the Congressional Black Caucus, who were angered by President Bush's veto of a major civil rights bill and by the Senate's inability to override it, threatened to vote against the deficit-reduction measure unless the Senate reconsidered the civil rights bill.

"If you are going to be irresponsible and deny civil rights, don't ask us to be responsible and pass a bill that lets you go home and declare victory," said caucus chairman Rep. Ronald V. Dellums (D-Calif.).

With Democrats scrambling for every last vote on the deficit-reduction bill, the caucus threat was taken seriously. House Speaker Thomas S. Foley (D-Wash.) met with black lawmakers for more than an hour yesterday to listen to their complaints and try to win their support for the budget package.

Last night, Foley and caucus members met again. As a price for supporting the budget bill, black lawmakers sought a commitment from Foley to push an unspecified legislative agenda next year to address the unmet needs of their communities in the areas of poverty, education and health.

"There's always a thousand trials," sighed a Democratic leadership aide, explaining that the budget bill is a fat target because it absolutely must pass and is going to be signed into law by Bush. "There's 535 people in this institution, and anyone can take a special interest in any part of the bill. And because it's so close, we can't blow anyone off, everyone's important."

But not every piece of business was so weighty as adjournment neared.

Late Thursday night, a gaggle of lobbyists monitoring the budget bill gathered in the Rayburn Room near the speaker's office to watch on a Sony Watchman a "Prime Time Live" television report that blistered members of the Ways and Means Committee for a junket they took to Barbados.

As they watched Rep. Thomas J. Downey (D-N.Y.) awkwardly try to justify the trip, the lobbyists shouted advice at the small screen. "Tom, just walk away, just end it," said one lobbyist.

And yesterday, actress Bo Derek caused a stir when she unexpectedly dropped by the House press gallery. Star-struck reporters stopped what they were doing, which at that point was not much, to ask Derek a few political questions -- an obvious ruse to keep her in the gallery.

"Should the voters throw the bums out?" asked one writer.

"I don't think they're bums," said Derek. "It's just a mess."

Lawmakers eager to get home agreed with that assessment.

Dancing her way off the floor as she sang "Show Me the Way to Go Home," Sen. Barbara A. Mikulski (D-Md.) sported a "Free the 101st Congress" button, a gift from Sen. Trent Lott (R-Miss.).

Lott said he was working on a new button. He said it would read: "Kill the 101st Congress."

Staff writers Bill McAllister, Helen Dewar and John E. Yang contributed to this report.