Around the world aboard a study ship

`DO not do chin-ups on shower curtain rod'' was one of the many special rules for our 100-day, around-the-world sea voyage. Another admonished not to use the netting over the swimming pool for a trampoline. This was Semester at Sea, an educational experience during which 67 oldsters (``seasoned travelers,'' they liked to call us) lived in close quarters with 365 college undergraduates, 74 faculty, staff, and families, and a couple of hundred Taiwanese crew. Half the time we were at sea taking classes and the other half ashore visiting the places we had studied. And though some found the courses a little easier than those on their home campuses, most applied themselves with some diligence, despite a general lack of privacy on board.

Between departure from Fort Lauderdale, Fla., in late January and arrival in Seattle in early May, the sparkling white SS Universe, an 18,100-ton passenger vessel owned by the C. Y. Tung Corporation of Taiwan, would come to be ``the great white mother'' to us, as one of the deans, Richard Stevens of the University of Colorado, put it.

``There is no other program in the world like this,'' he told a general meeting of students the second day at sea. ``This should be the best semester of your entire life,'' said Mr. Stevens, who was taking the trip for the fourth time.

When the late Mr. Tung initiated the idea of Semester at Sea, he had wanted to sponsor an international study ship that would attract students from many countries. He had originally acquired the huge HMS Queen Elizabeth for a floating campus, but when she burned and sank on the day of her rededication in 1971, the SS Universe was substituted. Originally sponsored by Chapman College in Orange, Calif., and later by the University of Colorado, the twice-a-year program is now run by the University of Pittsburgh.

Each voyage is individual, depending on the itinerary, the faculty, and the courses offered. For our trip, students could choose from 58 subjects ranging from anthropology to theater, with history, political science, and sociology linked to the areas visited. The mandatory core course, meeting every day, featured guest experts who explained the culture and customs of the people we were to meet.

The faculty came from large institutions like the University of Washington and smaller ones, such as Allegheny College in Meadville, Pa. It included what some called ``the gang of four'' -- a group of former Foreign Service officers. Judging from student comments, as well as our personal auditing, the instruction was generally of high caliber.

On arrival, students struggled up the gangplank with skis, surfboards, stereos, beach chairs, and sleeping bags. On departure, they carried souvenirs from around the world. They also carried memories of 10 foreign ports and myriad experiences. Some climbed mountains, some met gurus, some traveled in packs, and some went off to be alone.

On board ship, we ``ancient mariners,'' as we dubbed ourselves, had one lounge set aside for special lectures where we could also watch the nightly in-house news on closed-circuit TV. But most of the time we were with the students -- in classes, on the promenade deck (used largely for jogging), and in the cafeteria, where we could enjoy a variety of dining partners.

At our first port, Cadiz, Spain, we had a chance to book, through the ship's field office, excursions to Granada and Seville. From Piraeus in Greece we went to Athens and several Greek islands, and then to Istanbul. A large group flew from there to Israel, planning to rejoin the ship in Egypt. But when riots broke out in Cairo, the ship headed for Haifa, Israel, instead, on the recommendation of the US State Department. There we anchored outside the harbor while Israeli frogmen inspected the hull for explosives.

The Egyptians, apparently upset because the Universe had canceled her stop in Alexandria, delayed our trip through the Suez Canal and raised the price. Capt. Chang Chun-re, normally an even-tempered man, was not pleased. Nor was he amused when a student smuggled a chicken on board and turned it loose on the promenade deck.

En route to Bombay, many of us went on deck at 5 a.m. for fantastic views of Halley's comet. Colombo was as hot as Bombay, but Sri Lanka's interior was lush with vegetation and crowded with elephants.

A week in Hong Kong included an opportunity to visit the People's Republic of China. Our trip took us to Peking for five days, with a visit to the university and an the opportunity to talk to students. The Great Wall was even ``greater'' than we had imagined, and of course we were impressed with the Forbidden City, the Summer Palace with its marble boat, and our hotel, a two-year-old wonder of modernity. Many such new-style buildings are going up in Peking, a marked contrast to the daily early-morning gatherings of people to perform traditional tai chi exercises in the parks.

A three-day stop in Chilung allowed the Taiwanese crew a reunion with their families and the passengers a chance to view the National Palace Museum, full of mainland treasures, and to stay overnight at the all-marble Taroko Gorge. In South Korea, we spent a morning at an orphanage, where students from the Universe presented the facility with a check for $1,000 earned through charitable activities on board ship.

By the time we reached Kobe, Japan, our last port, the dollar had fallen drastically against the yen and many of us stayed close to the ship. With rail passes bought in Hong Kong, we rode the bullet train to Nagasaki and Hiroshima to pay our respects to the casualties of nuclear war.

The final two-week crossing of the Pacific included stormy seas and a hectic atmosphere in the classroom as students prepared for their final exams. Some didn't pass. Some, unfortunately, didn't care. Several of the older passengers earned credits for their courses, but most attended as auditors.

The experience was one to remember for a lifetime, as the dean suggested.

The food was substantial, sometimes exceptional (prawns, lamb chops, sirloin steaks), and regularly included first-class Chinese dishes. Entertainment on board included special dances (such as pajama parties), movies, and exercise facilities: basketball and volleyball courts, a weight-lifting room, aerobics, table tennis, and jogging. The 11,000-volume library could keep any passenger occupied the entire trip. The gift shop offered a variety of Semester at Sea items and brought aboard specialized gifts from every port.

One Sunday -- the only day without classes but with mandatory lifeboat drill -- a festival of Olympic Games was won by the crew, which, among other things, danced around in a Chinese dragon.

This fall the Universe sails from Seattle headed westward to Fort Lauderdale, with almost the same itinerary. Egypt and Greece will be replaced by Yugoslavia and the Soviet Union, where the ship will dock in Odessa on the Black Sea. Efforts are being made to invite a group of Soviet students to enroll in the Semester at Sea program, whose goal is to be truly international. On our trip, there were five Canadians and one student each from Brazil, Bermuda, Norway, South Korea, Switzerland, and Turkey. The Americans represented 146 institutions of higher learning, from Harvard University in the East to Mills College in the West. Practical information

The cost for students is between $8,500 and $11,000 for the semester, depending upon accommodations. Adults paid $9,550 for outside cabins, double occupancy. All cabins enjoyed private facilities. Land excursions were additional, but reasonable.

For more information about Semester at Sea, write to Institute for Shipboard Education, 2E Forbes Quadrangle, University of Pittsburgh, Pittsburgh, Pa. 15260; (412) 624-6021. The executive director is John Tymitz.