That changes with "Dr. Atl: Masterpieces," on view at the Centro Cultural Universitario Tlatelolco just north of downtown Mexico City. It is the first retrospective on Dr. Atl in Mexico in 27 years, meaning a generation of art lovers could get to know his work in depth for the first time.

His unmistakably forceful landscapes are familiar to average Mexicans as sort of visual footnotes to an era that saw Diego Rivera and Jose Clemente Orozco flourish internationally as muralists. Yet Dr. Atl's greatest pieces have resided mostly in private collections, making them rarely available for viewing to the public.

Born Gerardo Murillo in Guadalajara in 1875, Dr. Atl is one of the most accomplished and enigmatic figures from the golden period of modern art in Mexico.

REPORTING FROM MEXICO CITY -- He was a muralist, an educator and a civic activist who once helped save a colonial-era convent from demolition by moving in and living there. He published books, invented paints and signed his works "Dr. Atl," an imaginary honorific using the Nahuatl-language word for water.

The show is organized by the Blaisten Collection, a private museum founded by collector Andres Blaisten that sits inside the renovated university complex at Tlatelolco. It features more than 190 works, many of which are privately owned and not usually shown to the public.

The exhibit charts Dr. Atl's progression from early, more conventional landscapes through his adoption of the curvilinear perspective -- as the eye sees, he argued -- in rendering innovative and sweeping views of the Valley of Mexico.

The artist clearly was fixated on Mexico's volcanoes as both subjects to paint and sources of inspiration, particularly as he sought to push the very boundaries of the landscape form beginning in 1922.

By the end of his career, Dr. Atl wanted to radicalize landscape painting entirely with his theory of aereopaisajes, or aero-landscapes, in which artists would go up in planes, helicopters and eventually into space to create landscapes of infinity, of "supreme ascension."

Several of the most arresting paintings in the exhibit depict volcanoes at night, in a slanting perspective from high above. Glowing in aquas and purples, the paintings come close to creating a vertigo effect in the viewer, suggesting a peaceful eternal space.

Dr. Atl, who died in 1964 at the age of 88, worked in the classical method, hiking his way to peaks near the twin volcanoes of Popocatepetl and Iztaccihuatl to make swift sketches of the mountains and valley below (until he later lost his right leg). Then he would transform the quick sketches into brilliant paintings using oil and mixed wax-resin paints he made, calling them "Atl Colors."

It is a happy historical triumph that Dr. Atl was alive in 1943, when the Paricutin volcano began to poke out from the middle of a cornfield in the western Mexican state of Michoacan.

The artist recorded the rise of Paricutin as perhaps no other figure could, with dozens of sketches and paintings that showed the fiery and violent process of a once-in-a-lifetime geological phenomenon.

"For him it was important to walk among the volcanoes. He studied them from all angles," said Vannesa Bohorquez, director of the Blaisten Collection museum, during a recent visit to the show.

"If you didn't know the artist, you'd think these were done by a young [painter]," Bohorquez added. "You need a physical strength to do this, and this was a very old man who had lost a leg."

The artist was also a committed educator and activist, founding an open-air art school and living for an undetermined amount of years in the Convent of La Merced in the historic center of Mexico City in an effort to prevent its demolition. The building still stands.

"Dr. Atl: Masterpieces" is on view until April.

-- Daniel Hernandez

Photo: "La sombra del Popo," or "Popo's Shadow," a 1942 painting by Dr. Atl on view at the Centro Cultural Universitario Tlatelolco in Mexico City. Credit: Daniel Hernandez / Los Angeles Times