President Carter continued his slow journey through the Idaho wilderness yesterday, coming about as close as a president could ever come to genuine peace and quiet.

There were no handshakes, dignitaries to greet or protocol observed as the president, his family and a few friends floated gently down the Middle Fork of the Salmon River here. Security, while thorough, was low-keyed. Reporters, though on the river with him, were kept miles behind except for one or two token contacts with the presidential party.

The only sound at his campsite as he slept was the rush of the river.

The only comment he gave during the first two days of his trip was "how nice" it was not to have to make any comments.

The last reporters saw of him, Carter was bouncing in his 18-foot-long rubber raft over one of the river's small waterfalls, his arm wrapped snugly around daughter. Amy, to make sure she didn't fall out.

There was only one minor mishap. As the president was going over the falls, the handle to one of the oars guiding the craft snapped, delaying the trip for an hour while it was repaired.

Despite the million and a half acres of pine forest and cliffs surrounding this river, the Carters' three-day trip comes nowhere near "roughing it."

The large rubber rafts are expertly navigated by the most experienced wilderness guides in this area. The guides are equally proficient chefs, and served a deluxe dinner of marinated roast beef, clams, oysters, and strawberry shortcake prepared in a Dutch oven at the campsite.

The river changes moods every few miles. But it rarely gets rough at this time of year. Any danger comes not from raging rapids in the three-to-six-foot deep water, but from massive rocks and boulders that protrude from the river bottom. The guides zig and zag their craft through them with ease.

The ride over the Tappan Falls - a six-foot drop into foamy white water - is generally "as slick as a whistle," according to Dick Montgomery, who guided one of the three news media rafts over them yesterday.

As they traveled along with Interior Secretary Cecil D. Andrus and the Andrus family the Carters saw unspoiled territory.

The crystal-clear water is drinkable. There are no old tires or gasoline residues floating in it.

At the camsite, there are no beer cans left behind, no smelly outhouses, not even cigarette butts left as remnants of the 4,000 campers who make the 70-mile river trip each summer.

"There is no way you can have a bad time on the Middle Fork of the Salmon River," said Wallace T. Shiverdecker, a spokesman for the U.S. Forest Service here.

There was some concern at the start of Carter's trip about recent below-freezing nighttime temperatures and the intermittent hail and snow in the mountainous wilderness that greeted the first few hours of his journey.

But the president's first night out was relatively balmy, with temperatures never going below about 45 or 50 degrees. The sky was clear and starry and the moonlight was so bright that it awakened some campers during the night.

The president and his party set up their camp on a bend in the river in between two mountains 2,000 feet above the water after completing 30 miles of rafting at about four to six miles per hour.

They woke early and had a breakfast of pancakes, sausage and eggs. As the press raft passed him, Carter was warming his hands over a fire. He stopped to wave and grin.

The president's raft was accompanied by five other rafts, carrying other members of his party, the military aide with the famous nuclear war "black bag," Secret Service agents, forest rangers and communications people. No security protections were visible along the hills overlooking the river and no aircraft were visible over the president.

His advance team, usually grim looking, heavily armed Secret Service agents, was two Forest Service kayakers, who glided about a quarter mile in front of the presidential party.

A few reporters from the local newspaper, the Idaho Statesman, were spotted once or twice along the banks, but no more than seven or eight camping parties were seen during the second day of the trip. There are no roads in this area, though there are some airstrips. Hikers and mule teams can get through, but it is an arduous effort.

Carter completes his Idaho trip this afternoon and heads for Wyoming and the Grand Tetons for another week of vacation.