It was August and the sun pressed down upon Northwest Oklahoma, pushing temperatures past 100 degrees, creating a layer of heat that Charles Banks Wilson could see as he looked down the flat, straight ribbon of blacktop before him bounded on both sides by endless fields of wheat stubble.

The air conditioning in his Japanese compact strained, but the heat outside was too intense. The artist, perhaps Oklahoma's most famous, was sweaty and uncomfortable as he reached the only destination of State Highway 15: Red Rock, population 300.

This was Wilson's third trek across the state from his studio to Red Rock. This time, he told himself as he drove into the deserted town, he would sketch the 86-year-old Indian whose face, for months, had come to haunt him.

The Indian's name was Jim Petit and all the experts claimed that he was the last pureblood Otoe alive in America. There were other fullblood Indians whose veins contained Otoe blood mixed with Commanche or Ute or Chickasaw. But Petit was the only pureblood, 100 percent Otoe.

Forty-five years earlier, a group of white men from Texas and Oklahoma had chosen Jim Petit as the "Most Typical Indian of the Southwest." He was a beautiful man then, standing 6 feet, 3 inches tall, a muscular 250 pounds. His long braided hair was the color of a moonless night and his smooth skin was as red as western Oklahoma's rust-colored earth. Somewhere, Petit still had a packet of faded newspaper clippings to prove that once he was the model of how white men believed Indians should look.

But now the Eagle war bonnet that he had worn for photographers and the rainbow-color beaded breast plate were gone. Time had turned his hair white, yellowed the teeth that remained and transformed his arrow-straight frame into a bent and brittle reed.

"I am no longer a man," he had told Wilson during the artist's last trip. "No painting today."

This is why Wilson had returned. To try once again. He found the old Indian wearing a wide-brimmed white cowboy hat, sitting alone in the cluttered kitchen of his small frame house. Petit watched quietly as Wilson tapped on the screen door and stepped inside, not waiting for an invitation.

The Otoe listened as Wilson repeated the arguments that he had rehearsed during his drive. He talked about how he had painted portraits of more than 200 Indians. How he had become interested in pureblood Indians while painting murals at the state capitol depicting Oklahoma's history.

Wilson talked about his wife, Edna, who is a Quapaw. And he talked about the Otoes, recalling how they once roamed Missouri until they, like so many other tribes, were forced to move to a place the Choctaws called Okla (Red) Homa (People) land.

As he spoke, Wilson removed a pencil from his case and began to draw. The old Otoe said nothing; his face was a tired composite of sags and wrinkles.

When Wilson finished the drawing, the old man stood and spoke. He apologized, Wilson remembers, because he was not feeling well.

A week later, Petit, the last remaining pureblood Otoe on earth, died.

For the last decade, Charles Banks Wilson has used pencils and paper pads to record the quiet death of this nation's first inhabitants.

The project has consumed the 63-year-old artist, causing him to crisscross the Panhandle state searching for pureblood descendents of the 63 tribes sent to Oklahoma during a time when President Andrew Jackson wanted to corral all of the nation's redskins in one spot called Indian Territory.

There were dozens of different tribes speaking different tongues, following different customs--Delawares, Seminoles, Chickasaws, Cherokees. But to the white men, they were all just Indians. Some came voluntarily, wishing to get as far away from the white man as possible. A few rode steamboats up the Arkansas River to Fort Smith, Ark., where they bought horses and rode into their new homeland. Others, like the Creeks, resisted. They were marched to Oklahoma in chains and shackles by soldiers. Hundreds died, their bones forming what the Indians called a Trail of Tears across the South.

By the time Wilson's family came to Oklahoma, the white government had changed its mind about how to treat Indians. It once again wanted the Indians' land--so it took it.

Wilson's father, Charles, was a musician. During the early 1900s, while Oklahoma politicians were figuring out ways to get statehood for their territory, Charles was playing in traveling bands. He gave up his trombone, however, after he met Bertha Banks, a strong-willed woman who made it clear from the beginning that while she might fall in love with a wandering musician, she wasn't going to marry one and spend her life traveling between towns.

So Wilson became a house painter and he and Bertha moved to Miami, Okla., a mining town near the Kansas and Missouri borders. They went there for the same reason that thousands of others went to the new state: word was that a man could get a fresh start in the one-time Indian haven which finally became part of the Union in 1907.

Charles opened his own paint and wallpaper store, which suited his namesake son fine because the boy had become an insatiable doodler.

"I wasn't very good," Wilson remembers, "but I loved to draw. I used to draw under tables and on the backs of pictures."

It was not surprising that the young Wilson began drawing Indians. Few sights in Miami were as exciting to a small boy as an Indian powwow.

Wilson's home town had become a gathering area, of sorts, for 13 area tribes. Years before, thousands of Indians from across the state had gathered at various locations for powwows, usually at ration time when soldiers brought livestock for them to slaughter. The Indians would spend days chasing and killing the beef, dividing it and holding feasts. But while the Indians enjoyed the festival, the government saw it as an expensive waste of time and manpower since it had to keep troops at the powwow to oversee distribution and prevent trouble. So the government began shipping the Indians beef that was already processed and the number of huge powwows declined.

By 1920, there was no pressing reason for the 13 tribes in the Miami area to gather, but they did anyway, struggling to perserve a heritage that was quickly disappearing. And when they gathered, young Wilson, armed with school pencils, pads and paints from his father's store, was waiting. At first he drew the Indians in their traditional garb, chiefs wearing buffalo horn headdresses, dancers outfitted in beautiful feathers. His paintings sold well, helping him pay his way to the Chicago Art Institute to study. But he was not happy with his work, and during one of his frequent trips home, he finally understood why.

"One night, I became aware of the people watching the Indians dance. They were Indians too, but they were trying to live in a white man's world. A chief might have long braids, but he also might be wearing a derby. He might have an Indian blanket draped around his shoulders, but his shirt might be pleated in front with ruffled cuffs.

"I went to a powwow where a wealthy Quapaw had bought a merry-go-round for the Indian children to ride on. I began to realize that instead of painting young bucks chasing buffalo, I should be painting those little Indian children riding on that merry-go-round. That was the Indian of the day.

"Maybe it's something I learned at school, but I've always felt that an artist should record his own time," he says. "I suddenly realized that I was at the right place at the right time to record something very important. Something was happening to the American Indian that had never happened before. He was changing from the primitive free spirit into a social person. He was becoming a sophisticated member of modern America.

"It was almost as if I was seeing the transition of primitive man to sophisticated man. So, I decided to record it, to tell--through my art--what my eyes saw."

What Wilson saw and painted was not popular. "People asked me why I was making social comments. I wasn't making social comments. I was just painting what I saw, and sometimes people didn't like that."

A 1939 painting called Tribal Band is typical. It shows a group of Indians at a powwow dressed in traditional feathers, beads and buckskins but playing a mixture of old Indian instruments and sparkling saxophones. New Rich, another 1939 painting, showed an old Indian and his dog sitting on the steps of a dilapidated farmhouse. A new Cadillac is parked nearby.

He became known as "that Injun painter" and soon Indians were seeking him out. "I remember this Sioux man. He was a beautiful man with long braided hair. All the Indians liked to invite him to their powwows, because he looked like what they thought an Indian should be. Many of them had cut their hair, trying to adjust to the white world, but here was this proud old Indian with long hair.

"I painted a portrait of him and was driving him to friends when we hit a huge bump and it jarred both of us pretty bad. I looked at him and noticed that his hair had moved. He was wearing a wig. He had short hair too, but had bought a wig. I thought that was a sad comment about what was happening."

While he painted, Wilson learned as much as he could about the Indians. "Everyone told me to paint Henry Turkeyfoot because he was the last of the wild warriors. He was the type of guy who believed a fight with a knife or guns was child's play. So I found him and while he was posing, I asked him if he had really cut off a man's ears once. He nodded. I asked him why. 'Because he was my friend,' he said. 'I would have killed him if I didn't like him.'

"Everyone said Indians were humorless, stone faced, but I knew better. They were a lovely, fun-loving people."

A friend recommended Wilson for a job in New York as a comic strip illustrator. He took the job, but was restless. During a vacation home, he attended a Quapaw powwow.

"I saw her when I looked across the fire," says Wilson of his wife, Edna. "She was beautiful." They were married a short time later.

Wilson returned to New York and became a book illustrator, working on 28 books ranging from Treasure Island to The Story of Maple Sugar. But he was not happy. He decided to return to Miami, this time to organize an art department at a nearby state college. For 15 years, Wilson taught at the small school before quitting to open his own studio. He finally began doing what he had wanted to do: draw and paint full time.

"Being an artist is a congenital disease. You don't become one--you just are and there's not much you can do about it."

His career flourished. In 1962, the Oklahoma Legislature commissioned him to paint portraits of Oklahoma's four most famous native sons: Cherokee Chief Sequoyah, Indian athlete Jim Thorpe, comedian Will Rogers and Sen. Robert S. Kerr. Ten years later, the legislature hired him to paint murals in the state capitol depicting state history.

"I needed to paint a Wichita Indian in the mural and I did n't know what one looked like," he recalls. "I wanted to be accurate, so I went to the tribe. Its members told me that I must draw a pureblood because they were the only true Wichitas left. They drew up a list of acceptable subjects and that's when I began to realize that these tribes were being lost to antiquity. A breed of people were disappearing and no one was doing anything about it."

After finishing the state house mural, Wilson met with Thomas Gilcrease, a wealthy Oklahoman and art connoisseur. "I explained the project and asked him for funding, but he just laughed. 'There'll always be Indians,' he told me.

"No one was interested in my project, except Indians. They knew that purebloods were dying out and they encouraged me to sketch them, to prove that they had existed."

Depressed, Wilson turned to other projects until a few years ago when a mishap and a meeting with an old Indian convinced him to work full-time on his pureblood project. "I fell off a ladder and damn near killed myself and that made me realize that if I had something important to do, I damn well better get it done," Wilson recalls.

He also made a trip to Tulsa to draw one of the last pureblood Kaw Indians. "As I sketched that old man, he told me that he was the only Kaw left in the world who still knew how to speak his tribe's language. He told me that he talked English to his friends, but spoke Kaw to God because He had given him this beautiful gift.

"Here it was again. I began to sense what we were losing, what was passing before my eyes."

With the help of his wife and daughter, Carrie, a former Miss Indian Oklahoma, he began contacting every tribe in the state. He spent his nights and weekends riding along dirt roads, stopping at tiny farmhouses, talking to old Indians trying to find purebloods. "If I'd only started earlier, I could have sketched a Peoria, but the last one died before I really got going. I was angry at myself."

Soon, his inquiries paid off. "I found four Kiowa-Apaches, one of the smallest tribes in America. They were Kiowas but they traveled with Apaches, even though they never accepted the Apaches' ways. There are only four Kiowa-Apache purebloods alive today, two sisters and two brothers. They are the last of their tribe.

"Everywhere I went, people joked about my project. Everyone claimed there were lots of purebloods, like the Sac-and-Fox--Jim Thorpe's tribe--but when I began questioning the Indians, I discovered that there were no purebloods. I was about to give up when I learned of an old man who was not only a pureblood but was a descendant of chiefs of the Sac-and-Fox.

"I found this man in an old shack. Here was a man born to be a chief, but he was deaf and blind and poor and when I talked to his granddaughter and told her that I wanted to draw him, she said, 'Okay, but how much will we have to pay?'

"They had been beaten down so much they didn't even realize that I was the one who should be paying them," Wilson says.

"I began to look at my sketches and my old paintings and I noticed a slow transformation had taken place. When I was young, the Indians that I painted looked like wild coyotes, alive and eager. Now, they looked like old house-trained dogs.

"I hate to call anyone a defeated people. It's not fair to characterize an entire people. But what I saw was a people who still had not made the transition, a people still struggling to find a place in the white man's world."

Herman Viola, director of the Smithsonian's anthropology department and an expert on Indian tribes, says that "Wilson's project is really extraordinary and worthwhile." In the 1940s, the Smithsonian began an extensive program to photograph American Indians and record their customs. "We have photographs of various tribes, but what Wilson is doing has never been done before," says Viola, "because he is trying to document purebloods.

"I'm sure that within the next decade, all the purebloods will be gone. For that matter, most fullblood Indians will be gone," Viola says.

Of the 63 tribes, Wilson has sketched 57 pureblood representatives. "I've never sold any of the sketches. I want to give them to a corporation which, I hope, can claim a large tax deduction. Then, they can use the money that they saved to set up a scholarship fund for Indians that are three-quarters or more Indian blood." So far, he has no takers.

After all these years of searching and drawing, Wilson still struggles to explain why he is so concerned about sketching purebloods.

"I wish I had some pat answer, something really clever to say when I'm asked why I am doing this," he says. "But I'm not sure that I know. I just felt that something should be done.

"These are the last ones. Remington, Curtis and George Catlin painted the first Indians. Now, here I am. I've witnessed the transition. And now I want to record the end of a people, people who once ruled this nation."