CHICAGO -- It has become tradition at Wrigley Field. In the middle of the seventh inning, fans rise from their seats and join together in belting out the words to "Take Me Out to the Ballgame." A smiling caricature of Harry Caray looks on from the broadcast booth.

The late Caray became famous for leading the Chicago crowd in song, leaning out of the booth and waving his microphone like a conductor at times. In the years since Caray's passing, the Cubs have had a long line of celebrities and guests take turns trying to fill his shoes.

But how did this tradition begin? Well, it began on the South Side during Caray's days as a broadcaster for the White Sox. It is believed that his voice was pumped through the Comiskey Park speakers early in 1976 -- courtesy of then Sox owner Bill Veeck.

Let's have Caray tell his version of the story, as told to Fred Mitchell of the Chicago Tribune on April 3, 1994:

"That is the only song I know the words to," Caray was quoted as saying. "For the first few years [I was] with the White Sox, whenever [organist] Nancy Foust would play the song, I would sing it in the booth. Only Jimmy Piersall and our TV man would hear it. When Bill Veeck bought the ballclub, he looked over and could see that I was mumbling, 'Take Me Out to the Ballgame.'

"Veeck could see that about eight people below the booth were singing with me. The next night, unknown to me at the time, he hid a public-address mike. All of a sudden, during the seventh inning, all I could hear was my voice booming back at me along with a couple of thousand voices in the stands.

"When the game was over I went up to Bill and said: 'What the hell was that all about?' He said: 'Harry, I have been looking for 45 years for the right man. The first time I heard you, I knew you were the right man.' I began to puff up in flattery.

"'Yes,' Veeck said, 'I knew as soon as I heard you that the fans in the bleachers and the fans in the luxury boxes knew that they could sing better than you. If you had a good singing voice, you would intimidate them and they would not join in.'

"So, I said: 'Thank you, I think.' But he was so right. That gives you an idea of the public relations of a Bill Veeck."

A tradition was born, but Caray was not sure at first that it would continue when he moved to the Cubs' booth for the 1982 season. The late Arne Harris -- a long-time producer and director of WGN-TV's Cubs broadcasts -- told Paul Sullivan of the Chicago Tribune on Feb. 19, 1998, that Caray was initially hesitant to keep it going.

"He said, 'You know I sing this song at Sox Park. You think it will go over at Wrigley? It's a different kind of crowd, you know,'" Harris said. "I just laughed and said, 'Hey, give it a shot. If it goes it goes.' That's Harry. It was such a big deal that he came over to the Cubs, but the biggest thing on his mind was whether Cub fans would want him to sing."

Needless to say, it was a hit at Wrigley Field, and the tradition has continued since Caray's passing in '98.

At first, the Cubs weighed whether to play a recording of Caray singing for the Seventh Inning Stretch, but in spring of '98 the team announced it would have guests do the job. There have been plenty of great renditions, but also some doozies (most famously, Mike Ditka barking the words).

For the first game at Wrigley Field following Caray's death, Dutchie Caray, Harry's wife, led the crowd in song. She was greeted with a rousing standing ovation as the Cubs ushered in a new era, but kept the singing going in Caray's honor.

"Let him hear you in heaven!" she told the Wrigley faithful.