IN MEXICO, the early part of this century was tumultuous. It was the time of Pancho Villa and Emiliano Zapata, a time of strikes, revolution, transition. It was also the time of Agustin Victor Casasola, a press photographer who assembled an invaluable archive of those years.

More than 80 photographs from the Archivo Casasola now line the walls at the Fondo del Sol gallery. It's impossible to tell which pictures Casasola took, and which he collected from colleagues. But that's not important and it wasn't then: News is news, and there are no pretensions of art in these photos.

They are very affecting: the child soldier feigning defiance, weighted down with an ammunition belt. Young town criers -- voceadores -- sleeping in a crumpled heap, their faces mottled, their feet filthy. Zapata parading proudly on horseback. A dancer named Tina de Jarque performing in banana skirt, anklets and wristbands. And the pathetic boy prisoners, who contrast in their helplessness with the proud and powerful, and short- termed, presidents.

Casasola was Mexico's Mathew Brady, and as such, deserves a similar place of honor.

THE WORLD OF AGUSTIN VICTOR CASASOLA: MEXICO 1900-1938 -- At the Fondo Del Sol, 2112 R Street NW, through February 5, 1985. Hours: Wednesday through Saturday, 12:30-5:30.