Detroit, 1932. Diego Rivera, the Mexican artist, had been hired by Edsel Ford to execute his stylistic, controversial murals on the walls of the garden court at the Detroit Institute of Arts.

At the time, I was a grammar school student and had been chosen by my art teacher to attend a select weekly sketching class at the institute. The medium was charcoal, and the models were mostly the marble statues on display at the museum. The Mexican muralist’s frescoes were in brilliant contrast to the black-and-white charcoal sketches I was doing, and I was fascinated by his style and palette.

Rivera, in dirty blue overalls and paint-spattered shoes, worked on his famous frescoes, the ancient and difficult technique of painting with watercolors on wet plaster. On the east wall of the courtyard he depicted agriculture, on the west wall the Detroit River crowded with freighters. The south panel features the completion of a car, the north panel the stages in making an automobile engine. It was riveting to see the wet plaster come alive with color and teem with activity. Famous faces of 1932 jumped from the wall—a composite portrait of Thomas Edison and Henry Ford, as well as Edsel Ford, donor of the murals, shown with Dr.William R. Valentiner, director of the museum, all in Rivera’s vigorous style.

One time, during a class break, I was raptly watching Senor Rivera apply color on the wet plaster while he was standing on a low scaffolding before the north panel. He turned, smiled at me, and asked, “Little girl, would you like to help me paint?” I replied with an enthusiastic nod. He thereupon helped me up on the scaffolding and asked me to choose a spot. When I pointed at one of the figures at the left center of the huge panel and said, “There,” he gave me a brush filled with paint and let me daub for a time. After a while he murmured, “ Gracias ,” and I said, “Thank you” as he helped me back down to the courtyard floor. I continued watching the artist to see if he would alter my handiwork. He didn’t touch a thing but continued painting in an adjacent spot beyond “my” area on the sleeve of a factory worker.

Fresco is similar to watercolor in that once the paint is applied, the artist cannot change his mind, because colors immediately get muddy-looking. As a result, my brushwork endures unchanged.

In the few months that Senor Rivera took to execute his magnum opus at the Detroit Institute of Art, I never saw him invite any other student onlooker to assist him. As far as I know, I was numero uno as an apprentice.

I was thrilled to have been “assistant” to the great muralist, and for years Diego Rivera was my favorite painter. I did grow up to receive an