The Davis kids sometimes go without milk. Rents may go up in the T Street rooming house that Ellsworth Thomas manages. Mary and Arthur Sumpter cling to their Cadillac as a reminder of the good life -- but they can't afford to drive it much.

All over Washington, middle-income people are suffering the onslaught of rising energy costs. They are cutting back. They are buying oil and gas with food money, or money that last year would have bought a bike for a kid.

Interviews with families earning $13,000 to $20,000 show that energy costs -- for oil, gasoline, electricity and natural gas -- will increase about $500 for an average family this year over last, even after strong conservation measures.

"If it gets worse, then heaven help us," said Delois Davis.

"If it gets worse, we'll be in the poorhouse," said her husband, Herbert.

"We're already in the poorhouse," she said.

Americans have entered the era of high energy costs. The cost of home heating oil has gone up 176 percent since 1973, according to the federal energy department. Natural gas and electricity have gone up 95 percent in that time, and gasoline prices have risen 97 percent.

During the last 10 months, home heating oil has gone up 83 percent in the Washington area, from 48 cents a gallon at the start of last winter to 88 cents a gallon today.

It may go higher.

Economists say the costs for other fuels also will tend to rise. As consumers turn from oil, demand for other heat sources will raise costs for them, too.

George C. Batts, who has lived at 46 W St. NW for 21 years, converted from oil to natural gas heat last year when his old furnace wore out.

The conversion cost him $1,300 but he's glad he did it because gas cost him only $89 a month last winter. The 200 gallons of oil needed to heat his rowhouse would have cost more than $100 each month -- and closer to $200 a month this winter.

But the Davises, with a similar house at 723 G St. NE, paid $200 a month for natural gas heat last winter. They don't know why it was so high. They tried to keep the thermostat down.

"I considered changing to oil heat, the way the gas is," said Herbert Davis. "We have friends who have oil heat and they do better than we do (with gas)."

The Sumpters, two doors from Batts at 48 W St. NW, said they haven't considered changing from oil to gas heat.

"I think gas will cost more than that oil," said Mary Sumpter.

Even wood this winter may go for $100 a facecord (a stack 4 feet x 8 feet x approximately one foot). You have to put your name on a list to get a woodstove in most places. Maryland officials worry that the state forests will be ravaged.

The greatest impact of rising energy costs is on low-income people, officials say. According to the federal energy department, the average American family spent 5 percent of its total income on energy last year while low-income families spent more than 18 percent.

"It's a real hardship (on the poor), so we're all going to have to care about this," said Tina Hobson, director of the federal energy department's consumer affairs office.

"There were plenty of (low-income) people who had to leave their homes last year when oil went to 47 cents a gallon," said Janet Shorey of the Maryland energy office.

She said that, for the most part, these people moved in with relatives. There will be more such moves this year.

Since there is no immediate prospect that energy costs will stabilize or go down, adjustments are being made.

Some of them are painful.

People are falling behind in their mortgage payments to pay heating bills, according to Lillian Durham, a United Planning Organization officer here. Going without air conditioning. Compulsively roaming the house switching off lights. Spending precious dollars on home insulation. Swallowing their pride and going down to ask the government for financial help.

Screaming at each other in rage.

Delois Davis said that the pressure of $200-a-month gas heat bills has caused "arguments we wouldn't have had" between her and her husband, Herbert, a $13,000-a-year construction worker.

out of their income, the Davises pay $1,200 each year for natural gas, about $400 for electritcity, and more than $500 for gasoline.

That totals about $2,100 compared with an annual food bill of about $3,000 -- also rising.

The Davises estimate their energy costs have gone up between $300 and $500 during the last year, the fear that there will be a similar or worse increase this year.

The increases make her husband angry, Delois Davis said.

"It's a money-in-general thing. He comes home evil and he'll say nothing. Then he says, 'Why are you burning these lights?" Or during the winter he'll say, 'It's hot in here,' while maybe me and the kids are cold . . . At times I felt that he felt inadequate, that he (felt he) was not as much man as he could be because he was not able to provide all the things he could (before . . .

"I have to explain where every little penny went, which agitates me. He thinks the money should go further . . . "

No steaks or beef for the Davises. No beer for Herbert Davis. No new bike for 15-year-old son Quintin. No summer trips. No trip to Disney World, even though it had been much anticipated by the three children.

All this within the last year. It wasn't like this before.

"I don't know which way to turn," said Herbert Davis. "All I can do is try to hold it down the best I can."

His wife is unable to work because their 2-year-old son, Leon, has been sick a lot. She has stayed home to care for him.

When finances got especially tight last winter, Delois Davis went down to the United Planning Organization and received $250 to help pay her heating costs -- part of $400,000 in federal money the agency distributed in the city for heating bills last winter.

The one-time payment was a god-send.

"I felt I had lots (of money) for the kids' clothes they had gone without," she said. "I went out and blew a whole lot. (My husband) got angry at that. But . . . my shopping was a way of letting off some of the things I felt, too."

Ellsworth Thomas sat on the porch of the rooming house he manages at 524 T St. NW, talking with his friend, Monroe Walker.

"Forty-nine cents a gallon last year, now it's 90 cents," said Thomas.

'That's a lot of money," said Walker.

Rooming house rents have been going up to cover heating bills and there may be an increase at 524 T, the pair said.

"Might not be a cold winter," said Thomas.

"Liable to be cold this winter," said Walker.

"Cold last winter," said Thomas. "Every time I came around the . . . oil man would be here.

Mary and Arthur Sumpter have a combined income of "maybe $20,000," she says. "Put 'poor' down there. Poor. Poor. Poor."

She doesn't have the air conditioning on.

"I don't want to have the air conditioning on. I don't mind a little sweat. We're going to sweat in the summer and freeze in the winter."

She is assistant manager for a food company. He is a construction man, a cement finisher. Their house is fairly well insulated. They would like to add storm windows, but can't afford them.

They heat with oil. She would like to get a second 100-gallon tank, so that they could fill up with more oil before prices go higher this winter.

But then she reasons that it would be of little use. The saving would be a one-shot deal, probably wouldn't pay the cost of the second tank.

The Sumpters have cut down on car travel, cut out a vacation they had planned.

But they haven't yet taken out all the slack. "I could catch the bus [to work], but I don't feel I want to," she said. She said she may change her mind.

As for their late-model Cadillac, a big gasoline user: "I feel that when I work hard, if I want something I try to get it."

However, she noticed when a neighbor "got scared" and bought a small, gas-efficient car. It made her think.

There are bright aspects to all this.

"My electric bill this August is one fifth what it was a year ago," said D.C. energy chief Chuck Clinton. "That's because (my family) decided we didn't need air conditioning. And I'm still alive here at the end of September.

"It's the difference between $32 and $180 a month. I'm prepared to argue that [Americans in general] can do without whole-house central air. As we get into the energy shortage, we are being forced to rethink what is actually essential to our lifestyle . . . . We've developed expectations that are just unreasonable.

"We don't need to be that cool."