I was first introduced to Geco in 1993, when MOMA mounted an exhibition of Latin American artists. I remember loving her work, but with few examples on view, I hadn’t realized the extent of her creativity, and more or less forgot about her – though not completely, because hers is the only work from that show I can still picture clearly. The current Guggenheim exhibition, closing on Sept. 10, fills in the story, and demonstrates just how powerful this artist was. Born in Hamburg in 1912 as Gertrud Goldschmidt, in 1939, at age 27, she escaped Nazism by fleeing to Venezuela, where she made her permanent home – though she did travel to the States. As a trained architect and engineer, Geco created (mainly) sculpture that with thin rods draw in space patterns so gorgeous that their beauty becomes emotional resonance, and the illusion of movement and change become mesmerizing. The parallax (graphic lines replicated along different parallels) creates ever-changing moiré patterns (caused by parallel lines crossing each other with divergent angles) as the viewer sees the piece from different directions. Transparency morphs into volume, static shapes morph into the illusion of movement, lines become volumes, metal becomes delicate and fragile, and proportional tension becomes a dance of space and wonder. Arriving at her signature use of linear rods early in her career, she constantly discovered new effects by the addition of new materials, shapes or structural systems. At the end of her life (she died in 1994 at age 82), when she could no longer make large sculpture, Geco created collages of inter-woven paper strips that echo her 3-dimensional sensibilities of movement, spatial flickers, and transparency, as do the drawings, prints, artist’s books, and graphic and textile designs that she explored throughout her career. Except for the four photos before the early painting, photos are posted in approximate chronological order.