Rosa Ponselle will be 80 next Saturday. Her birthday will be an occasion to celebrate one of the greatest voices and artists of the century. But lots of people must have thought Giulio Gatti Casazza was crazy back in the fall of 1918 when he announced that the Metropolitan Opera was going to give Verdi's "Forza del Destino" for the first time in Met history with Enrico Caruso, which was fine, and Giuseppe DeLuca - fine again - and a soprano named Rosa Ponselle.

Rosa who?

Even the insiders had never heard of her. If they had known the whole story the "insiders" would have been even more horrified. This "Ponselle" had been born in Meriden, Conn; she had never been to Europe, much less studied or sung in opera; she was 21 years old, and she had never been on an opera stage in her whole life. Besides, she had fainted the first time she sang an audition for Gatti. What in heaven's name was the tough opera manager thinking of?

Gatti was gambling. No American-born singer who had not been to Europe for study and performance in opera had ever sung a leading role at the Metropolitan. What was there in this tall, good-looking Italian-American girl that made him take such a chance?

Well, first of all, Caruso, the biggest name in the opera world in those days, had heard Ponselle sing and had said to her, "You will sing with me at the Metropolitan." Besides, it wasn't exactly ture that "no one had ever heard of her."

When she was 10 years old, Rosa Ponselle, who was born on Jan. 22, 1897, sang in her church choir. Her voice was so big and so beautiful that they told her please not no sing - it drowned out the others. So after a couple of years, she and her sister, Carmela, had gone to New Haven to sing in Malone's Cafe, an establishment as popular with the Yalies in those days as the Naples Pizza is today. At Malone's they loved the Ponrillo Sisters, which was their real name, the name their father Bernardo had brought with him when he emigrated to Meriden to start a grocery and bakery.

The Ponzillo Sisters didn't stay long at Malone's, however. Soon they were touring in vaudeville, where their big numbers included the Barcarolle from "The Tales of Hoffmann." Carmela singing Musetta's Waltz Song from "Boheme" with Rosa playing piano, and Rosa singing "Kiss Me Again" from Victor Herbert's big hit, "Mille, Modiste." But what really brought down the house was a special arrangement - and it must have been very special - of the two of them doing the final trio from "Faust"! Since the girls couldn't afford long dresses, they sang in shirtwaists and skirts, which gave them the billing of "Those Tailored Girls" when they were not plugged as "Those Italian Girls."

From the Keith circuit, the sisters made it to the Palace, which was the top spot. It was also in New York City, and Rosa came to the attention of a voice teacher there named William Thorner, a man who obviously knew just what to do with the spectacular voice that God, as Geraldine Farrar loved to say, had put in Rosa Ponselle's throat.

Gatti-Casazza was not bothered by Ponselle's fainting that day. What he could not forget was the sound of her voice. So he had her come back for another try and then made his fateful decision. He also changed her name from Ponzillo to Ponselle. "You have to succeed," he told Rosa before her debut, "or I will have to take the boat back to Italy." But when Nov. 15, 1918, rolled around, Ponselle wished she were anywhere but backstage at the Metropolitan where she had heard the two operas the previous season ("Butterfly," with Farrar and Caruso, and "The Love of Three Kings," with Muzio and Caruso).

"I arrived at the theater in a state of cold panic," she says of that debut night. "I was numb. I couldn't lift my arms. The madkeup man had to apply the paints on my face. I thought, "This is it, I'm going to die on the stage." I don't know how I performed at all; it was a miracle, an absolute miracle. I sang through the first 10 minutes or so praying to God every moment."

Apparently her prayers were answered. "The highlight of the performance was the singing of Enrico Caruso as Don Alvaro," James Huneker wrote in The New York Times, "and the brilliant debut of Rosa Ponselle. She possesses a voice of natural beauty that may prove a gold mine; it is vocal gold anyhow, with its luscious lower and middle tones, dark, rich and ductile. Brilliant and flexible in the upper register, yet a sweet, appealing, sympathetic voice, well placed, well trained."

Six weeks later, after she sang the taxing role of Rezia in Weber's "Oberon," Huneker wrote again, ". . . here dramatic temperament, musical intelligence, above all, her beautiful natural voice and its remarkable range, brating silvery soprano - her scale is seamless, so equal are her tones from top to bottom."

That's the way it went from then on Ponselle sang at the Metropolitan for 19 seasons. In 22 roles, she sang 258 times in the big house and another 108 times on tour. Other than a few performances in three seasons at Covent Garden and a single season at the Maggio Festival in Florence, the Ponselle opera career is contained entirely within those Metropolitan years. That was not, however, the extent of her singing. Her recordings, which reach back to her earliest days, cover a period of 40 years, including two that RCA Victor came down to make in her home outside of Baltimore. And in the golden days of live music on radio, Ponselle was one of the great and greatly anticipated soloists on the General Motors and General Electric hours. She sang regularly with leading symphony orchestras, and in concerts in which here glamorous personality and wide repertoire in half a dozen languages kept her one of the most popular of all artists.

Her opera repertoire ranged from the pure classic lines of Mozart's Donna Anna, Spontini's "La Vestale" and Bellini's "Norma" to the realism of Santuzza in "Cavalleria Rusticana" and Madeleine in "Andrea Chenier" by Giordano. The Leonora she sang at her debut was the role she sang most often in her career, followed closely by Santuzza, Gioconda, Leonora in "Trovatore," and Norma. She became one of the greatest Violettas in "Traviata," and a highly controversial Carmen. To hear both these roles in live recordings today is to discover much of the astonishing genius Ponselle poured into her conceptions of such famous, standard parts.

Although she retired from the Metropolitan 40 years ago this season, the number and quality of Ponselle recordings make it possible for those who care about the greatest in singing to hear clearly, and in many ways, just what is was that so triumphantly vindicated Gatti-Casazza's daring venture nearly 60 years ago. It was a vocal art, trained and polished in this country, that remains unsurpassed today, an art whose possessor opened the door for all the "Made in America" singers who have followed.