The D.C. City Council has been known to "gum the bullet" - instead of biting it - every now and then when the time comes for making tough decisions. But that was not entirely the case last week when the Council faced the task of reducing the mayor's proposed 1979 city budget in order to set aside money for property tax relief.

Casting aside the previous "gentlemen's agreements" to stay out of each other's business, the Council cut more than $1 million from the mayor's operating budget. That was enough money to slice in half the city's public information office, to reduce by one-third the size of the mayor's auditing staff and his governmental efficiency team.

The Council's loud refrains of financial austerity quickly softened, however, when it came time to deal with the Council's own budget, from which less than $150,000 was cut. The Council not only agreed unanimously to spend more than $144,000 to add 13 people to its own staff - a GS-6 "constituent services assistant" for each Council member - but also voted to give every member but the Council chairman $300 a year to pay for cookies, coffee and donuts when folks drop by to visit.

"We're an elected body and we don't have enough moeny to buy a cup of coffee," lamented Nadthe P. Writer (d six) as she introduced the cookie jar amendment to the budget bill.

Arrinton dixon, the Ward 4 Democrat who moonlights as an insurance man to help make financial ends meet agreed with Winter, chiming in that her approach was necessary, "if citizens don't want a (Marvin) Mandel situation where elected officials have to depend on those who have the money to buy coffee."

Dixon's reference was to the assertion by some that the legal problems of Marland's governor, which resulted in his conviction on federal mail fraud and racketeering charges, stemmed from the financial woes of Mandel's $25,000-a-year salary.

D.C. City Council members get a little more than that. With the 7.05 per cent pay raise recently granted most city employees Council members' salaries are now $28,444 a year. (The Council chairman gets $10,000 more). In addition, Council members can receive up to $360 a year in mileage reimbursements for in-town travel.

Marion Barry may be able to have his political cake and eat it, too, in the aftermath of last week's rejection by the Council's finance and revenue committee of legislation that would have required commercial properties in the city to be taxed at a higher rate than residence.

That approach, called "split-rate" or "classified" property taxation, has been one of the cures proposed by those who think city homeowners are getting squeezed more on property tax bills than businessmen. It is also, as expected, strongly opposed by city businessmen, some of whom think it will drive more businesses out of the city.

Barry said the rejected the plan, which was sponsored by David A. Clarke, before the committee partly because he has his own plan which will soon be unveiled. The Barry plan will create two tax rates, but not by raising the currently uniform rate to a higher level for businesses, as was likely under the Clarke bill. Rather, Barry will lower the rate for homeowners and keep businesses the same rate.

That's good for homeowners, because they get lower taxes and a split level. That's good for businessmen, because they don't get higher taxes. It's also good for Barry, because he gets to take credit for it all. Under the Clarke bill, the mayor - whose place Barry hopes to take in 1978 - would have been responsible for proposing any change in tax rates. And that, of course, doesn't help Marion Barry's political future.

When Douglas E. Moore left the reception in the mayor's office last week for visiting Zulu King Goodwill Zwelithini and Queen Mantfombe. Moore came away with something he hadn't expected - a Zulu war cry to possibly use as a slogan in his announced campaign for Council chairman in 1978.

The word is "Bayethe" (pronounced Baa-YEH-te) and, according to Moore and an information attache accompanying the chief, it was once used by the famous 19th century Zulu military leader Shaka Zulu to send his troops into battle. The word means "Bring on the enemy and we will crush them," Moore says.

"I think I could use that in my campaign," a grinning Moore told a reporter, after closing a toast to the visitors with a cry of "Bayethe!"

"I could just say, "Bring on the Board of Trade and I will crush them," Moore said.