ALTHOUGH THE ENTIRE POINT OF THE MOVIE...:

Ah, but who wouldn't love that song?

Well, let's see: for starters, the studio executives, the film's producer and director, the music publisher, and the lyricist.

It was the first number in the movie, and the last to be written. Harold Arlen and E Y Harburg had written what Arlen called the "lemon drop" songs - "Ding-Dong! The Witch Is Dead" and the other Munchkin novelties so well suited to Harburg's particular brand of lyric whimsy. But Arlen knew little Dorothy needed a big tune, an emotion-wringing ballad, and the awesome weight of it seemed to paralyze him. "I can't tell you the misery that a composer goes through," his lyric writer, Yip Harburg, said years later, "when the whole score is written but he hasn't got that big theme song that Louis B Mayer is waiting for." Arlen and Harburg had a 14-week contract with MGM. It was Week 14 - at the end of which Mr Mayer would cease paying them. And yet Arlen couldn't get the tune. "I was getting anxious," he recalled. "My feeling was that picture songs need to be lush, and picture songs are hard to write."

One day he and the missus decided to catch a movie at the famous Grauman's Chinese Theater. His wife Anya drove; Harold was a bag of nerves over his ballad block. They were tootling along Sunset Boulevard, round about where the original Schwab's drugstore was, when the tune more or less fell out of the sky and into his lap - a "broad long-lined melody" that he scribbled down on the jotting paper he kept in the car precisely for such moments. "It was as if the Lord said, 'Well, here it is, now stop worrying about it!'"

He got home at midnight and called Yip Harburg: "Come right over. I've got the tune!"

There was one slight problem: To the composer's dismay, the lyricist didn't care for it. That big octave leap on the first two notes sounded all wrong to Harburg. "Oh, no, not for little Dorothy," he said. "That's for Nelson Eddy." He thought Arlen's grandiloquent formal theme stuck out like a sore thumb among all the playful "lemon drop" stuff like "If I Only Had A Brain".

Sometimes when a lyric writer doesn't warm to a tune, the composer withdraws it and writes another. But Arlen determined to defend his corner. So they went round to Ira Gershwin's house.

Arlen, Gershwin and Harburg were good friends. The latter two had been in high school together, and written a column for the school newspaper called "Much Ado by Yip and Gersh". In the Thirties, the grown-up Yip and Gersh wrote songs with Harold, when George Gershwin's obsession with Porgy And Bess was getting to brother Ira and and he was in the mood to moonlight with Harburg and Arlen on some revue numbers. So both men were happy to have their chum pronounce one way or the other. Arlen played the tune, very grandly, symphonically, like a fellow who knows he's written something important. And Gershwin couldn't really hear it. So he asked him to pick it out on the piano with one finger. "See?" said Ira. "There's nothing wrong with that."

"You're right," conceded Harburg. "That's fine."

He had a lot riding on the song. For a jobbing lyricist on a movie assignment, he was as emotionally invested in The Wizard Of Oz as Ira's brother was in Porgy And Bess. The rainbow was Harburg's principal contribution to the project. Or as his son Ernie put it, in the title of his fascinating book about his father, Who Put The Rainbow In The Wizard Of Oz? Answer: Yip Harburg. There's no such meteorological phenomenon in L Frank Baum's original book, but, as Yip conceived it, for little Dorothy in dirt-poor hardscrabble Depression-era Kansas the rainbow was the only colorful thing she'd seen in her life. It's what gave the studio the idea of shooting the Kansas scenes in monochrome, and reserving full blazing color for when Dorothy gets to Oz.

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