(Si Liberman is a renowned travel and feature writer)

It was billed as an Enrichment Panama Canal/Mexican Riviera Cruise. And during 15 days on the 2 ½-year-old, 1,080-passenger Crystal Serenity, we attended almost daily lectures by experts on everything from avoiding seasickness, jet lag, insomnia and heart attacks to covering the war as a foreign correspondent, selecting a competent physician and how to avoid mid-life and late-life sex problems.

In a way, you could say it was like being in school again. Only this time there was no homework or tests to worry about, and attendance was strictly voluntary. Lecturers included a former Mayo Clinic physician, retired Los Angeles Times foreign editor, British TV newscaster, a caricature artist and a former Cleveland hospital administrator.

Between stops in Key West, Aruba, Puntarenas, Costa Rica, and the Mexican resorts of Huatulco, Acapulco and Cabo San Lucas, my wife and I also joined others at complimentary computer classes conducted by crew members.

Speakers used video and slides to make their points, graciously answered questions and stuck around afterwards to answer more questions and mingle with passengers.

More and more small luxury cruise lines are traveling this route, offering interesting, entertaining and life altering information to passengers interested in widening their horizons and perhaps rub elbows with a celebrity speaker or expert.

“As for celebrities,” says Kristin Turner, Crystal’s corporate entertainment manager, “we use quite a few. Marlin Fitzwater, the only press secretary in U.S. history to work for two presidents (Reagan and Bush senior), has been doing two cruises a year with us as a lecturer. Among others, Art Linkletter, Linda Ellerbee, the prize-winning TV newscaster and cancer survivor, Fox news analyst and Middle East expert Marc Ginsburg and Clint VanZandt, a former FBI profiler who’s a regular on MSNBC.”

Speakers aren’t paid per se, she confided, but receive free luxurious accommodations for themselves and a companion. That seems to be standard cruise line policy, a survey of competing shipping companies indicates.

“Depending on tenure, qualifications and length of the speaker’s assignment, however, we may pay the speaker’s air fare as well,” Turner added.

“We look for professional types -- persons in the public eye who easily can connect with guests. I may contact them directly or work through a manager. I try to line up people you’re likely to see on TV or read about. That’s what makes this job so interesting and challenging.”

Current events and celebrity talk usually draw the biggest audiences. Also, discussions about the ship’s destinations and sightseeing suggestions.

If you have an expertise and can enlighten and/or entertain a mature audience and would like to apply for a cruise speaker assignment, Turner offers this advice:

“Send me a tape or DVD of your lecture. It should be in front of a live audience, though.” Her address: c/o Crystal Cruises, 2049 Century Park East, Suite 1400, Los Angeles, CA 90067.

One of the most prolific cruise lecturers is Ruth S. Abramowitz, a health columnist and former Cleveland hospital administrator who lives in San Diego. She does four or five Crystal cruises a year, and has also lectured on Holland America, Radisson, Celebrity and Oceania lines.

Passenger reaction is both gratifying and at times surprising, she says. In her “Intimate Moments – All About Midlife Sex’’ talk, she recalled with a smile, “I state that for women intercourse adds to the health of vaginal tissues and for a man ejaculation may promote prostate health. After my lecture a man ran down to the podium with pad and pencil in hand and asked me to write that down so he could give it to his partner.”

What happened during one of his cooking demonstrations shocked everyone, says James Reaux, frequent Radisson cruise ship guest chef and lecturer who is the former executive chef of the five-star Boca Raton Resort Hotel in Florida.

“A passenger stepped up and insisted on tasting a super hot habanero pepper even after I warned her. Needless to say, she threw up in front of the entire crowd.”

According to Bruce Good, Seabourn Cruise Line public relations director, “Lecturers get to Seabourn by three main methods -- by applying to us directly through the mail, through referrals from other lines or other contacts in the industry and from agents who specialize in enrichment and destination speakers. . . We will not accept speakers who read from bullet point notes, regardless of the extent of their research.

“We’ve had everyone from Walter Cronkite to Michelle Phillips to Tom Van Essen, who was New York City’s fire marshal on 9/11.”

Silversea, Radisson Seven Seas and the Norwegian cruise lines work with talent agencies or speakers’ bureaus to line up speakers.

“We’ve had best-selling authors, distinguished scholars, business and political leaders, explorers, pilots, artists and photographers,” said Gina Finocchiaro, a Silversea spokesperson. “Ones that come to mind include Kathy Sullivan, the first woman to walk in space; Judith Miller, former New York Times reporter, and the former speaker of the House Commons, Betty Bootroyd.”(CQ)

On a seven- to nine-day cruise, the Norwegian Cruise Line vessels may have two or three lecturers, spokesperson Lauren Cohen points out. “Among others, we’ve recently had Stephen Bauer, a White House military aide for five presidents, and maritime historian John Maxtone-Graham.”

“We do not offer lectures on our ships,” Jennifer de La Cruz, Carnival Cruise Line public relations representative, said. “Our emphasis is on participatory activities. The only sort of exception is our Alaska cruises where we do have an excellent naturalist on board.

“The premium and upscale lines all use guest lecturers to one degree or another, but among the mass market lines it is going to be much more limited. In Carnival’s case,. we don’t use them at all.”