Ralph Waldo Emerson Jones came to the small black college in this north Louisina town by a case of mistaken identity, but he stayed for 51 years.

For 41 of those years, he was president of the school that became Grambling State University, an institution best known for stocking pro-football teams and setting up programs for its students who came with less than college-level skills.

Instead of the title President Ralph Waldo Emerson Jones, he preferred a nickname that, he says, "settled" on him: Prez.

Everyone calls him Prez, regardless of whether Jones is in his office with its perpetually open door, on the baseball diamond where he has coached the school's winning team for 51 years, or anywhere a Grambling alumnus spots Jones on his far-ranging travels for the school.

Prez, who has become one of the nation's leading figures in black education, retired last week at the age of 71, leaving a university on 300 gently rolling, pine-shaded acres that faces an uncertain financial future.

The university also is going through a period in which the existence of black colleges is being questioned by those who want to merge them with white institutions, not only for the sake of economy but also for the sake of integration.

To survive under such stress, said Prez, you have to learn to "hold your cool and still press on."

At his final commencement last week, Prez presided with three of his familiar assets: a powerful bass voice, a roaring laugh and a chorus of "amen's" during the speeches. He received hearty praise for his work for Grambling while professors wept into their academic hoods, but he remained dry-eyed. After all, he wasn't supposed to be there.

Ralph Waldo Emerson Jones was one of five men in Southern University's Class of 1925 - the school's first class. All five men were interviewed for jobs at Grambling by the school's founder, Charles P. Adams, a strapping protege of Booker T. Washington who stood 6-feet-10 and weighed 310 pounds.

"Four of the men being interviewed were star athletes, star football players," said Jones. "I was the star scrub because I sat on the end of the bench. I was a tiny little sucker.

"Being big, Adams thought big, the other men were very large, and Mr. Adams took quite a while to talk to them and he took down their names and addresses, but to be courteous, he took my name and address, too. But Mr. Adams wrote a letter to me, and I came, and when he saw me - a 120-pound youngster, 250 miles from home with no money and not knowing anybody - he said, 'you're not the one I thought I was getting.'"

Nevertheless, Adams kept the 19-year-old man at the school, which was then a trade school and training institute for teachers that didn't become a four-year college for nearly two more decades.

In his first year, Jones was assigned to teach biology, mathematics, physics and chemistry; start a band; coach football and baseball; and be dean of men and registrar. His monthly pay was $50 in script, but because the person who cashed the note could keep 28 per cent, Jones' take-home pay was $36.

The school's standard of living was comparable to Jones'. He had to get the football equipment and 17 band instruments on credit from Sears, Roebuck and Co.

In addition to his mathematics degree, Jones held certificates in tailoring, plumbing, auto mechanics and mechanical drawing. To raise money and to clothe himself, he opened a tailoring and pressing shop, and in his spare time, he helped chop firewood and raise food in the school's vegetable garden. He also wrote the alma mater to the tune of "Maryland, My Maryland."

"How I did it," I don't know, but I did it, and I enjoyed it," said Jones, whose school consisted of five frame buildings without electricity or running water.

"We didn't get electricity until 1936," he said. "They did not want to put in electricity; they said it would not pay, so I went to a good friend at the Ruston Power Plant. The Ruston City Council had said no, but this friend took it upon himself to run a line out here, and I never will forget when we turned on the lights. Each room had a little bulb in it.

"How happy we were. However, it took quite some time before I stopped trying to blow out an electric bulb every night."

Two years later, Grambling, which by then had been a state school for a decade, got its first state money for a building program. Among the structures errected was a neat brick president's home, and Jones and his new bride moved in from their former residence, the school library. He has been there ever since.

He is nearly bald, and he isn't any taller than when Charles P. Adams interviewed him for a job more than half a century ago. He is still fit because he is a coach and a teetotaler who eats sparingly and works out daily with an exercycle and vibrator in his home.

His wife died in 1953, and his two sons have moved to Baltimore, so Prez lives alone, but he won't be in the president's house much longer; he is getting ready to move into a brick house he is building south of campus. In the president's home, shirts and ties are neatly folded on guest-room beds, empty boxes are waiting to be filled, and his baseball uniform - No. 30 - has been put into a closet for the last time.

When Jones became president, the school was still known as the Louisiana Negro Normal and Industrial Institute, said Dr. Ernest Benson, a business professor. "He got the legislature to change it to Grambling College by telling them to imagine what would happen if the football team were trying to make a touchdown. He told them that by the time the crowd got through saying, 'come on, Louisiana Negro Normal and Industrial Institute' the other team would have won. And it worked."

Jones tried to keep such an upbeat attitude during the early years of his tenure, but "becoming Grambling's president wasn't anything to jump up and rejoice about," said Prez as he sat at his dining-room table, which he thumped to underscore his statements. "You had to start from nothing because you had nothing to build on."

Though it became a state school in 1928, the legislature voted no money for Grambling until 1932, when it appropriated $9,000, followed in the next two years by $54,000. To supplement this money, the drama students staged plays and readings, and other campus groups put on minstrel shows and concerts, and Prez kept wooing officials in an attempt to bring more money for his school.

This is still his paramount concern. This spring, the Louisiana Legislature has voted to take care of Grambling's deficit, but it will be approached again for more money to keep the school open.

Grambling's first champion was Huey P. Long, who backed the drive for state-school status. His brother, Earl, was another early booster, and he visited the campus frequently. Jones characterizes both men as "precious people, and you can put that down in big capital letters."

There were other powerful supporters then, but they were less demonstrative because "it wasn't the revolutionary period," said Prez. "There were those in power who knew what we were doing was right; they just didn't speak out openly. You knew within yourself that this was the system, you see, but you felt that somebody it would change. You always looked to the brighter side."

At the bottom of this situation was racism. It was never stated openly, "but you knew it," said Prez, pronouncing each word slowly for added emphasis.

Despite the tight budget, Prez set up a center to train teachers and other workers to go out into rural Louisiana, where no specialists had ever been before, to improve the lives of poor black people.

Some people who benefited from this program came to Grambling but without the skills normally expected of college-level students. For these young men and women Prez set up the school's general studies program of remedial education.

"Those general studies course pick them up right where they are - on the seventh or eight-grade level - and you have no idea how some of them come out of there and how they improve," said Prez.

Only a small amount of integration has taken place - 40 of Grambling's 4,000 students are white - and Prez believes Grambling will remain predominately black, and that Grambling and schools like it will continue to fill a need.

"There are so many young blacks that would not be understood by a predominatley white faculty because they would not understand the background of these young people and, really, they do not understand the language, that's the big thing."

When Ralph Waldo Emerson Jones became Grambling's president in 1936, he had to give up all his outside activities except one: coaching the baseball team.

"I had to do something for exercise, and I had to do something to keep close to the students, and I have about 25 to 30 young men on my team, and others try out for the team, and many more come out to the games."

"In recent years, he would still pitch batting practice, and he had a good fast ball and an outstanding curve," said Eddie Robinson, Grambling's football coach and athletic director since 1941. "He also hit balls into the infield for infield practice."

Jones helped Robinson develop and promote events like the Bayou Classic, an annual game with Southern University in the 70,000-seat Louisiana Superdome in New Orleans, and he encouraged Robinson to try for other things, such as out-of-town trips and caoching seminars, to help the team and the school. Despite the fame the school's football program eventually got, both men put academics first.

"Here, we have a rigid rule that a player has to keep up a minimum grade-point average to stay on the team. And we don't bend that rule, even if it hurts us - as it has," said Robinson.

One student who absorbed Prez prioities was Richard Michael St. Clair, a defensive end with the Cleveland Browns who had played that position for the Tigers and returned to Grambling this spring in his off-season to finish his degree in management.

"Prez was always with us, on the planes and on the buses. He was always the first one on and the first one off. I used to sit next to him at the pre-game meals, and he always gave me his meat off his plate."

Ralph Waldo Emerson Jones came to Grambling with pride in his career and in his ancestry.

His father was principal of a school in Lake Charles, where Prez was born, and, later, the first dean of Southern University. Prez received his name from his mother, who had read all of Emerson's works and kept them on a bookshelf at home. "I was so proud of my name," Prez laughed "and I bragged that I was named for Ralph Waldo Emerson until I found out that he was an alcholic."

He learned about history from his mother's father, a slave who bought his freedom with $300 he earned from crops he raised on land his master had given him.

Through most of his career, Jones was able to imbue his students with his sense of awe about education and self-improvement, and, he said, this paid off during the '50s and early '60s, when students could see blacks make gains because of the civil rights movement.

But from 1967 through 1972, campus fury "threw us back quite a bit," he said. "Some outsiders came in and organized students in terrible protests, but some of the things they were protesting about were so immaterial and immature. It wasn't the war that got them mad; they were angry, just angry, just stirred up."

There was intermittent violence on the campus in the all-black town, "but I stood my ground; I didn't run," said Prez, "even though they threatened me. In 1967 and 1968, we had to put out 22 students because they were terrorizing the place. Once I had gone to Hawaii with the football team, and when I walked into may hotel room, the red light was on. Dr. Cole had called me because there was another demonstration."

During this period, comedian-activist Dick Gregory came on campus, "and the auditorium was packed because the students thought he was really going to be radical and revolutionary," Prez chuckled, "but he really laid them out for being so immature, and he emphasized the importance of getting an education. He really surprised them."

Prez infiltrated their meetings with his spies and, in his words, "played cool" until the campus calmed down.

"Later, a lot of them came back here, and several that we had put out came up to me down at Southern at a football game, where I was sitting on the bench with the team. They called me to the fence and hugged me, and they said that they were wrong."

"I can't step into Prez' shoes," said his successor, Dr. Joseph Johnson, at Grambling's commencement. "His shoes are too large for me."

Johnson, who had played basketball here under Robinson, came back from the University of Colorado at Boulder, where he had been executive assistant to the university president. He will take over July 1, and Prez will enjoy his first vacation since he came to Grambling. He has been invited to travel with groups of educators to Iraq, Indonesia and the Soviet Union, and Doubleday is asking him to write his memoirs.

Prez's last offical act at Grambling was the commencement, where he led the procession of faculty members and graduates into T.H. Harris Auditorium.

"I wrote a letter of resignation in October," said Dr. Ardell Pringle, an assistant professor of teacher education, as she walked toward the auditorium on the hot, bright May morning, "but then I talked to Prez, and I tore it up."

Following the teachers were the 244 bachelor's degree candidates, 41 of whom were finishing with honours, and 18 students receiving master's degrees.

When they all sat down in the cool auditorium, Prez faced them and said, "In 1937, we had no place like this to have a commencement. We had to move the straw out of th e cow pavilion and have the commencement there."

During the ceremony, he was unfazed as he heard Dr. Floyd L. Sandle, Grambling's dean of general studies, apply to him a description of black college presidents made by Charles V. Willie and Marlene Y. Macleish:

"The success of the black college president has been sure but unsteady. Yet, they managed to endure and to overcome.They and their schools have survived because they faced adversity with ingenuity and continued to have hope."

While others on the stage cried, Prez was animated, muttering, "amen," and, "that's right," during the speeches and saying something personal to every student as he handed out the black-bound diplomas. He pulled one Nigerian man out of the line for special applause, and he praised a woman who finished her bachelor's degree while putting three of her children through college.

Finally, it was Prez's turn to speak, and his powerful voice never wavered.

"Do not let the name of Grambling drag in the dust," he told the graduates. "If you hear anybody bad-mouthing Grambling, spit on him or hit him. When I've traveled, I've worn my Grambling jacket, and I've walked sideways so everybody could see it.

"I just talk about Grambling all the time - and about you. I can't help it, it's just in me. It's a part of my spirit and a part of my soul.

"Goodbye to everybody."

Prez raised his right arm as if in benediction while the organ began the recessional hymn, "A Mighty Fortress Is Our God."