Some vacationing friends took a week off recently to sleep in a pup tent and spend most of their waking hours climbing over, under and across innumberable large rocks. A few others made plans to cycle 100 miles on a 10-speed, or possibly tackle the rapids in a canoe. Or both.

After brief (very brief) consultation with our bodies, my wife, Jeannette, and I decided against such dubious forms of respite, mostly because they sounded less like respites than work.

We opted instead to use some of the proceeds from two years of "real" work for a "real" vacation - one which did not involve climbing, tent-pitching, paddling, pedaling, dishwashing, bed-making or anything vaguely reminiscent of work.

Hence, we took a cruise.

It was not only our first real escape since we'd married and moved to Washington two years ago - it was also our first cruise. And, as I said, it felt good.

The word "felt" is used in its most sensuous sense. Our recent eight-day cruise from New York to Bermuda and back provided sufficient good feelings to take the edge off just about every form of nerve cell found within our rest-starved, trembling bodies.

Five hundred miles out of New York, and the sea is bluer than the sky. You can actually see through the water and breathe the air. Salt proliferates in both. We're on the starboard rail, watching for the flying fish that appear out of the wake every so often for 20-yard glides just above the surface.

I gaze dreamily at Jeanette. She is gazing dreamily at the flying fish. "What's wrong?" I ask in distress. "Is this not romantic?" I point out the beautiful sunset.

"I am falling asleep," she says, her eyelids at half mast.

That's the other good feeling (and obviously, sometimes not-so-good) we discovered aboard the Princess: that soothing rocking of the ship. Until the advent of good stabilizers and convenient drugs, it often used to make ship passengers sick. Now it mostly puts them to sleep.

Sensory jackpots abound aboard the Princess, which, as "the newest ship in the world," might be somewhat of a disappointment to those expecting to find all that old-fashioned woodwork, formality and exquisitely choreographed decadence they might have found aboard Cunard's old Queen Elizabeth in its heyday.

The Princess, said the brochures, is the ship of the future. If that's true, the ships of the future will rely heavily for their appeal on plastic, aluminum, informality and plenty of (as opposed to memorable) food. On the Princess, they were all means to a worthwhile end.

The plastic and aluminum comprise most of the ship's aultramodern decor - at its best in the vessel's four bars and restaurant. The informality refers to both crew and passengers. The crew, all British except in the restaurant, was not merely friendly and helpful. They didn't just serve you. The also talked to you.

The passengers, in both dress and manner, were all all-around non-formal bunch. Tuxedos and long gowns showed themselves only at the captain's cocktail party Sunday night - even then they weren't required and many didn't wear them.

Couples dominated the passenger list, primarily middle-aged and older. There were also quite a few young couples, several mother-daughter, aunt-niece parties, a few families with young children and several "groups" - one from the Lovely Baptist Church in Philadelphia.

As for the food: While the quality of what was served was about average, the quantity was beyond both belief and digestion.

If we'd wanted (and we often did), we could have been served a continental breakfast in our cabin daily at 7 a.m. "Early bird coffee" was also served on deck at 7. Late-sitting breakfast in the ship's Meridian Room restaurant came at 8:45, with enough courses to keep us swallowing until 10. Boullion was served in the ship's Wahoo Bar at 11 a.m., hamburgers and frankfurters on deck five from noon to 3, late-sitting lunch at 1:30, and dinner at 8:30 p.m. And winding up nightly, a midnight buffet complete with an ice sculpture, fresh watermelon and nary a dish to wash.

For all this - plus the sea breezes, the island, and entertainment - we paid $625 each. Only drinks and tips were extra.

We traveled with Diane and Jack Osborne of Clarksville, N.J., a couple of good friends who also happen to be Jeanette's aunt and uncle. The day before we were to leave, Diane told us that Cunard had erred and that she and Jack were without a reservation.

(The Osbornes' reservation, listed in the name of Mr. and Mrs. John W. Osborne III, had been accidentally canceled by Cunard when our travel agent asked the line to cancel the reservations of Jack's parents - Mr. and Mrs. John W. Osborne II.)

Not to worry, said the travel agent. Diane and Jack were given a huge stateroom equipped with color television, refrigerator, two twin beds, a convertible sofa, three large portholes and a bathtub. They were, in a word, upgraded.

There's always a possibility, we discovered later, that cruise lines will upgrade passengers - even if reservations haven't been lost. This occurs because passengers pay for a "grade and not a particular room, we were told, and when the time comes to make room assignments the line will occasionally find itself with extra rooms of a higher grade that would otherwise go empty. So they may be assigned without additional charge.

It's called goodwill, and Diane and Jack told us it felt good.

Like our friends, Jeanette and I bought a room on the fifth of six passenger decks, but we received no more than we'd expected. Our stateroom contained two convertible sofa beds and a vanity, but neither bathtub nor portholes.

While in port (two days each at St. George and Hamilton), we went ashore, after breakfast for sightseeing, swimming or shopping - with the help of those fantastic motorbikes one can rent on the islands. We usually came back for lunch, leaving the ship afterward for a second trek ashore - to the Holiday Inn for tennis, to the Botanical Gardens for walking, the luxurious Southampton Princess Hotel for gawking, or just about anywhere for swimming.

The Bermuda Islands themselves are beautiful. The sand is really pink, and the beaches - if you do some looking - can be just as peaceful and deserted as they are pictured in some magazines.

On our last night at sea, we showed up in one of the ship's lounges for bingo. The final game was called "snowball" because that's what the prize does after each winnerless night - and there had been six such nights. The prize was $1,030.

We went at the urging the night before of one Brian Egan, the ship's chaplain for the week and the only person we'd met on board whom we knew. The day we boarded, Jeanette recognized the 52-year-old Benedictine priest as the engimatic leader of folk masses in which she sang as a high school student in New Jersey. He spent most of the trip with us.

The place was packed. Tension mounted as the game leader called off the numbers that everyone - including Jeanette and I - hoped would pay for the whole trip and then some.

Somebody up front called bingo. Instant and complete envy.

It was Father Egan. Instant guilt.

But it was all so appropriate. As Egan arrived at dinner that night, the people at his table - most of whom were Jewish - sang to him. They sang, "If I Were A Rich Man."

Father Egan said it felt good.