PINKISH painted cherubs cavorting on the arched ceiling gaze down with the same innocence that rises in the voice of Sen. Henry I. Bellmon (R-Okla.).

"What is a modern strategic bomb?" the senator asks. A man at the table explains by spouting numbers that no one understands.

Well, now, Bellmon wonders, "Are we buying another neutron bomb?" The man with the numbers says no. Besides, he adds, "It's a classified matter."

Bellmon shrugs a thin smile on his face, but he understands.

"No controversy at all on that," says Sen. J. Bennett Johnston (D-La.), the chairman. He is right.

Other senators at the long table nod, as another defense weapons issue is resolved and another hefty expenditure - in this case, the amount is classified - approved by the subcommittee.

Before the afternoon is over, in the course of a three-hour meeting, the appropriations subcommittee on public works approves spending about $10.2 billion.

The money is for federal dams and navigation projects, for nuclear weaponry, for energy research, for the Tennessee Valley Authority and other agencies.

Important items, all. The cherubs on the ceiling are mute, but they must marvel at the sights and sounds in this tiny subcommittee meeting room in the Capitol.

The chairman reads from a ledger-like sheet, quoting amounts appropriated by the subcommittee, amounts sought by the president, amounts appropriated by the House.

The other senators follow along on their sheets as Johnston reads between puffs on a long, thin cigar. He jumps from item to item, reponds to an occasional question and entertains motions for adoption.

They are approving this huge outlay of money with hardly a question or a challenge. Senatorial staffers sit to one side on folding chairs, reading along on their own copies of the ledger-like sheet. A few lobbyists sit behind them, understanding little but the numbers involving their own special interests.

At the table, papers shuffle constantly. Sharp yellow pencils move quickly along the columns of numbers Senators lose their places.

Clifford P. Case (R-N.J.) interrupts to go to bat for money for a couple of projects in his state. Not to worry. Johnston replies, it's taken care of in a section of the bill Case seems to have overlooked.

Milton R. Young (R-N.D.), aging and frail, is poised, wide-eyed, extra-alert for the moment he can break in and seek money for projects at home that are not covered in the bill. He smiles when he succeeds.

Warren G. Magnuson (D-Wash.) arrives late, sits transfixed with his elbows propped on the table for 25 minutes, says nothing, gets up and *leaves. Bellmon is serious - he's the only one in shirtsleeves.

Walter (Dee) Huddleston (D-Ky.) eats a package of peanut butter crackers. Ernest F. Hollings (D.S.C.), who cracks jokes, whispers to an aide that when he puts in for retirement he'll say he worked for the Army Corps of Engineers.

Johnston keeps things moving. If he took off his halfmoon glasses and put garters on his shirtsleeves he would look like a riverboat gambler, bidding, calling, collecting and paying off.

THE CHERUBS may marvel, but this is a part of the process of government. It is one small part of the complicated step between the collection of a tax dollar and its return to the economy as a government expenditure. Much of it is deadly dull, but it is the guts of congressional power. Seats on House and Senate appropriations committees are coveted because they give a legislator a direct link with the way money is spent in his or her district or on programs of interest to the legislator.

This power to help an agency, boost a friend or direct a policy makes forces of subcommittee chairmen such as Johnston. Hollings, Sen. William Proxmire (D-Wis.), Reps. Jamie L. Whitten (D-Miss.), Daniel J. Flood (D-Pa.), George H. Mahon (D-Tex.) and 20 others in the House and the Senate.

As Johnston's subcommittee moves along on this public works bill, the advantages of membership show up.

Young, finding his moment ("while we have everyone here.") and Quentin N. Burdick (D-N-D.) plead for money to go ahead with controversial Bureau of Reclamation dam in their state.

They don't get a yes - the Garrison project is the subject of a thorny dispute with Canada - but they don't get a no. Johnston says he'll send it on to the full committee.

Mark O. Hatfield (R-Ore.) says, "I offer nothing for my own state," but wants money for a coastal harbor development project in California. "We'll put in $150,000," says Johnston, persuaded.

Bellmon wants in increase in spending on the McGee Creek dam project in Oklahoma. "All agree it will be a major improvement," he says. The subcommittee adds $3 million to the appropriation.

James R. Sasser (D-Tenn.) wants language to express subcommittee support of TVA land-buying activity at a dam site and to express concern about rising TVA electricity rates. He gets it.

Huddleston explains how money had been cut from a floodwall project at Dayton, in his state, because the town had not guararnteed putting up a share. The guarantee is now in, he reports, and he is granted the $1 million he seeks so the floodwall can move ahead.

Actually this is a picture of restraint. This year subcommittee members have made fewer last-minute pitches for homestate boodle than usual.

Before they quit for the day, however, Johston wants to clean up one more matter. He's having the term "public works" taken out of the title of the bill. He doesn't say so - doesn't have to - but the term is read by some to symbolize waste and greed.

Its new name is the Energy and Water Development Appropriation Bill. The cherubs still smile benignly as the subcommittee adjourns.