The death of 89-year-old Violette de Mazia on Sept. 20, 1988, marked the end not simply of a life devoted to art and education, but of the idiosyncratic founding era of the Barnes Foundation.

For 37 years, she had presided over the renowned collection housed in the limestone-sheathed Merion mansion that had been the realm of her late benefactor, collaborator, and close companion, Dr. Albert C. Barnes. No one, perhaps not even Barnes himself, had a greater impact on shaping the foundation's course in the last half of the 20th century than de Mazia.

Formed by Barnes in 1922 to house his extraordinary collection, the foundation was intended first and foremost as an educational institution devoted to conveying an art-appreciation program developed by Barnes, educator and philosopher John Dewey, and, eventually, de Mazia. But while Dewey and philosopher Bertrand Russell, who spent time on the Barnes payroll, had credentials to back up their pedagogical musings, de Mazia's background was, well, vague.

She arrived at the foundation in the 1920s, hired to teach French. But Barnes quickly spotted her keen intelligence and capacious memory, and it wasn't long before she was teaching in the art-education program, collaborating with Barnes on books, and accompanying him on collecting trips to Europe.

Slight of frame, the Paris-born de Mazia cultivated personal theatricality. Because of an eye allergy, she wore dark glasses. Her multiple rings included a jangly thumb ring. She selected clothing and pinned on flowers that emphasized aspects of paintings discussed in her lectures. She implied that she had studied at prestigious French schools, but admitted at a 1960s court hearing that she had not.

After Barnes' death in 1951, his widow, Laura, and the never-married de Mazia stayed as far away from each other as possible. De Mazia completely controlled the foundation's art program as director; Laura Barnes, foundation president until her death in 1966, ruled over the arboretum.

Over the years, the decisive factor in Barnes matters was de Mazia's interpretation of what "the doctor" would want. Issues spelled out in the foundation's governing trust indenture were subject to de Mazia's interpretation. And as detailed as the indenture was, it was perhaps just as ambiguous.

For instance, nowhere does it require the actual teaching of classes. It stipulates that no paintings shall be moved, but does so in a section discussing art hanging in Barnes' residence, not the foundation's famed galleries. It prohibits art students from copying works in the galleries, but does not bar photographic reproductions.

All such issues were decided by de Mazia, who became the foundation's last link to Albert Barnes. No reproductions of artwork, no conservation work, no catalog, minimal visitors, no children: all were de Mazia's edicts, citing the Barnes' ambiguous (or mute) founding texts or long-ago comments.

Former foundation trustee David W. Rawson told The Inquirer in 1989: "In the vacuum of no one else having any idea, de Mazia very successfully could say, 'I am the true apostle and I know.' Who was going to gainsay her?"