On Broadway: only a handful of modern choreographers have so completely embraced the spirit of show dancing in their work as Alvin Ailey.

You hove to wonder how different the dance world would be if Alvin Alley had never come to New York to take a job in a Broadway musical. Would we have had a Revelations--and would it have looked the same? Would we have had the Ailey company, or the school? There's a good chance the answer to those questions is "no."

In 1954, as detailed in Jennifer Dunning's wonderful biography, Alvin Ailey: A Life in Dance (Da Capo Press, 1998), Ailey was in Los Angeles mourning the recent death of his mentor and employer, Lester Horton, and struggling to keep the Horton company together. He had already turned down a job in the chorus of House of Flowers, a new, Caribbean-flavored Harold Arlen musical based on a Truman Capote story.

Set on a lush tropical island, where two fierce but funny madams compete for a slice of the sluggish local economy, House of Flowers had a large, and largely black, cast. When the show changed choreographers during its out-of-town tryout, Ailey got yet another job offer. This one he couldn't refuse: featured dancer, with a steamy duet for him and Carmen de Lavallade, and "Slide, Boy, Slide," a showy solo.

When House of Flowers opened in New York, it didn't impress most of the critics, and it lasted only a few months. But it launched the skyrocket career of Diahann Carroll. And it provided paychecks for lots of young black dancers, several of whom would ultimately help change the race of dance in America.

For Ailey, House of Flowers served as an introduction to the bubbling New York dance scene--he sampled classes with legends like Martha Graham, Katherine Dunham, and Doris Humphrey. When the show closed, he supported himself with occasional dance and teaching gigs. Then he landed a role in Arlen's next musical about the Caribbean, Jamaica.

This one starred Lena Home as an island curie who dreams of big-city life. By the time it opened in 1977, calypso was no longer exotic and that, along with Horne's popularity, allowed Jamaica to run for 558 performances. According to Dunning's book, Home encouraged the dancers to take advantage of the steady pay, and the presence of talented colleagues to mount some of their own choreography. Alley took the bait, and used some of his $150-a-week salary to rent one of the modern dance world's favorite spaces, the auditorium at the 92nd St. Y, and put on a show. It was March 30, 1958, and Horne was in the audience when Blues Suite galvanized the crowd and announced the arrival of a major choreographer. The rest, as they say, is history.

Ailey had already choreographed for the Horton company, and there's no doubt that he would have continued to make dances whether he'd joined House of Flowers--and whether or not Jamaica had settled into a long run. But there can be little doubt that it would have taken the seeds of the Alvin Ailey American Dance Theater a longer time to germinate if not for the handy soil of the Imperial Theater and an Actors Equity paycheck.

Ailey's Broadway experience was important in another way: Only a handful of modern dance choreographers have so completely embraced the spirit of show dancing. Ailey had fully experienced the thrill that ripples through a Broadway theater when a line of spiffy dancers sashays in unison towards the edge of the stage. He had absorbed the effect of artful lighting and costumes, and he understood the power of stopping a show cold with an "11 o'clock" number. The finale of Revelations is perhaps the best snob number ever devised. Modern dance was hardly lacking in theatrical know-how, but it had a tendency to mistrust the show-biz impulse. Marrying his Broadway education with his modern-dance roots, Ailey did modern with a dash of glitz, gaining a faithful base of fans along the way.

In 1969, he returned to Broadway, this time as a choreographer. The show was La Strada, based on the Federico Fellini movie, with a score by Lionel Bart, the composer of Oliver! The director was the brilliant Alan Schneider, who had directed the first American production of Waiting for Godot but had never before done a musical. Alas, La Strada flopped big time and that was the end of Alley's Broadway career. By then, Revelations had been created; the dance company was touring here and abroad.

Alvin Ailey managed very well, thank yon, without another musical. It was Broadway's loss.

Sylviane Gold has written about theater for Newsday and The New Yolk Times.